U.S. patent number 7,945,859 [Application Number 12/336,581] was granted by the patent office on 2011-05-17 for interface for exchanging context data.
This patent grant is currently assigned to Microsoft Corporation. Invention is credited to Kenneth H. Abbott, Steven J. Fluegel, Joshua M. Freedman, Dan Newell, James O. Robarts.
United States Patent |
7,945,859 |
Abbott , et al. |
May 17, 2011 |
Interface for exchanging context data
Abstract
A facility for exchanging context attributes is described. A
characterization module receives an invocation request to provide
an attribute value that was generated by a requesting attribute
consumer. The received invocation request identifies the attribute
whose value is to be provided. In response to receiving the
invocation request, the characterization module provides a value
for the identified attribute to the requesting attribute
consumer.
Inventors: |
Abbott; Kenneth H. (Kirkland,
WA), Fluegel; Steven J. (Hastings, MN), Freedman; Joshua
M. (Mercer Island, WA), Newell; Dan (Medina, WA),
Robarts; James O. (Redmond, WA) |
Assignee: |
Microsoft Corporation (Redmond,
WA)
|
Family
ID: |
34743613 |
Appl.
No.: |
12/336,581 |
Filed: |
December 17, 2008 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20090094524 A1 |
Apr 9, 2009 |
|
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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11075529 |
Mar 8, 2005 |
7478331 |
|
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09692507 |
Oct 19, 2000 |
6920616 |
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09541328 |
Apr 2, 2000 |
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09541326 |
Apr 2, 2000 |
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09216193 |
Dec 18, 1998 |
6466232 |
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Current U.S.
Class: |
715/740; 709/201;
706/45; 715/744 |
Current CPC
Class: |
G06F
21/00 (20130101); G06F 3/016 (20130101); G06F
9/54 (20130101); G06F 1/163 (20130101); G06F
3/011 (20130101); G06F 2221/2149 (20130101) |
Current International
Class: |
G06F
3/00 (20060101); G06F 17/00 (20060101) |
Field of
Search: |
;715/736-648,740-748,866
;709/201,223,224 ;706/45,61 |
References Cited
[Referenced By]
U.S. Patent Documents
|
|
|
3973251 |
August 1976 |
Stephans |
4283712 |
August 1981 |
Goody |
4458331 |
July 1984 |
Amezcua et al. |
4569026 |
February 1986 |
Best |
4815030 |
March 1989 |
Cross et al. |
4905163 |
February 1990 |
Garber et al. |
4916441 |
April 1990 |
Gombrich |
4970683 |
November 1990 |
Harshaw et al. |
4991087 |
February 1991 |
Burkowski et al. |
5032083 |
July 1991 |
Friedman |
5133075 |
July 1992 |
Risch |
5201034 |
April 1993 |
Matsuura et al. |
5208449 |
May 1993 |
Eastman et al. |
5214757 |
May 1993 |
Mauney et al. |
5227614 |
July 1993 |
Danielson et al. |
5237684 |
August 1993 |
Record et al. |
5251294 |
October 1993 |
Abelow |
5267147 |
November 1993 |
Harshaw et al. |
5278946 |
January 1994 |
Shimada et al. |
5285398 |
February 1994 |
Janik |
5317568 |
May 1994 |
Bixby et al. |
5327529 |
July 1994 |
Fults et al. |
5335276 |
August 1994 |
Thompson et al. |
5353399 |
October 1994 |
Kuwamoto et al. |
5388198 |
February 1995 |
Layman et al. |
5398021 |
March 1995 |
Moore |
5416730 |
May 1995 |
Lookofsky |
5454074 |
September 1995 |
Hartel et al. |
5470233 |
November 1995 |
Fruchterman et al. |
5471629 |
November 1995 |
Risch |
5481667 |
January 1996 |
Bieniek et al. |
5493692 |
February 1996 |
Theimer et al. |
5506580 |
April 1996 |
Whiting et al. |
5513646 |
May 1996 |
Lehrman et al. |
5522026 |
May 1996 |
Records et al. |
5535323 |
July 1996 |
Miller et al. |
5537618 |
July 1996 |
Boulton et al. |
5539665 |
July 1996 |
Lamming et al. |
5544321 |
August 1996 |
Theimer et al. |
5553609 |
September 1996 |
Chen et al. |
5555376 |
September 1996 |
Theimer et al. |
5559520 |
September 1996 |
Barzegar et al. |
5560012 |
September 1996 |
Ryu et al. |
5566337 |
October 1996 |
Szymanski et al. |
5568645 |
October 1996 |
Morris et al. |
5572401 |
November 1996 |
Carroll |
5592664 |
January 1997 |
Starkey |
5601435 |
February 1997 |
Quy |
5603054 |
February 1997 |
Theimer et al. |
5611050 |
March 1997 |
Theimer et al. |
5642303 |
June 1997 |
Small et al. |
5646629 |
July 1997 |
Loomis et al. |
5659746 |
August 1997 |
Bankert et al. |
5675358 |
October 1997 |
Bullock et al. |
5689619 |
November 1997 |
Smyth |
5689708 |
November 1997 |
Regnier et al. |
5701894 |
December 1997 |
Cherry et al. |
5704366 |
January 1998 |
Tacklind et al. |
5710884 |
January 1998 |
Dedrick |
5715451 |
February 1998 |
Marlin |
5717747 |
February 1998 |
Boyle et al. |
5719744 |
February 1998 |
Jenkins et al. |
5726660 |
March 1998 |
Purdy et al. |
5726688 |
March 1998 |
Siefert et al. |
5738102 |
April 1998 |
Lemelson |
5740037 |
April 1998 |
McCann et al. |
5742279 |
April 1998 |
Yamamoto et al. |
5745110 |
April 1998 |
Ertemalp |
5751260 |
May 1998 |
Nappi et al. |
5752019 |
May 1998 |
Rigoutsos et al. |
5754938 |
May 1998 |
Herz et al. |
5761662 |
June 1998 |
Dasan |
5769085 |
June 1998 |
Kawakami et al. |
5781913 |
July 1998 |
Felsenstein et al. |
5787234 |
July 1998 |
Molloy |
5787279 |
July 1998 |
Rigoutsos |
5790974 |
August 1998 |
Tognazzini |
5796952 |
August 1998 |
Davis et al. |
5798733 |
August 1998 |
Ethridge |
5806079 |
September 1998 |
Rivette et al. |
5812865 |
September 1998 |
Theimer et al. |
5818446 |
October 1998 |
Bertram et al. |
5826253 |
October 1998 |
Bredenberg |
5831594 |
November 1998 |
Tognazzini et al. |
5832296 |
November 1998 |
Wang et al. |
5835087 |
November 1998 |
Herz et al. |
5852814 |
December 1998 |
Allen |
5867171 |
February 1999 |
Murata et al. |
5873070 |
February 1999 |
Bunte et al. |
5878274 |
March 1999 |
Kono et al. |
5879163 |
March 1999 |
Brown et al. |
5881231 |
March 1999 |
Takagi et al. |
5899963 |
May 1999 |
Hutchings |
5902347 |
May 1999 |
Backman et al. |
5905492 |
May 1999 |
Straub et al. |
5910799 |
June 1999 |
Carpenter et al. |
5911132 |
June 1999 |
Sloane |
5913030 |
June 1999 |
Lotspiech et al. |
5924074 |
July 1999 |
Evans |
5937160 |
August 1999 |
Davis et al. |
5938721 |
August 1999 |
Dussell et al. |
5942986 |
August 1999 |
Shabot et al. |
5945988 |
August 1999 |
Williams et al. |
5948041 |
September 1999 |
Abo et al. |
5953718 |
September 1999 |
Wical |
5959611 |
September 1999 |
Smailagic et al. |
5963914 |
October 1999 |
Skinner et al. |
5966126 |
October 1999 |
Szabo |
5966533 |
October 1999 |
Moody |
5966710 |
October 1999 |
Burrows |
5971580 |
October 1999 |
Hall et al. |
5974262 |
October 1999 |
Fuller et al. |
5977968 |
November 1999 |
LeBlanc |
5983335 |
November 1999 |
Dwyer, III |
5991687 |
November 1999 |
Hale et al. |
5991735 |
November 1999 |
Gerace |
5995956 |
November 1999 |
Nguyen |
5999932 |
December 1999 |
Paul |
5999943 |
December 1999 |
Nori et al. |
5999975 |
December 1999 |
Kittaka et al. |
6003082 |
December 1999 |
Gampper et al. |
6006251 |
December 1999 |
Toyouchi et al. |
6012152 |
January 2000 |
Douik et al. |
6014638 |
January 2000 |
Burge et al. |
6023729 |
February 2000 |
Samuel et al. |
6031455 |
February 2000 |
Grube et al. |
6035264 |
March 2000 |
Donaldson et al. |
6041331 |
March 2000 |
Weiner et al. |
6041365 |
March 2000 |
Kleinerman |
6044415 |
March 2000 |
Futral et al. |
6047301 |
April 2000 |
Bjorklund et al. |
6047327 |
April 2000 |
Tso et al. |
6055516 |
April 2000 |
Johnson et al. |
6061610 |
May 2000 |
Boer |
6061660 |
May 2000 |
Eggleston et al. |
6064943 |
May 2000 |
Clark, Jr. et al. |
6067084 |
May 2000 |
Fado et al. |
6081814 |
June 2000 |
Mangat et al. |
6085086 |
July 2000 |
La Porta et al. |
6088689 |
July 2000 |
Kohn et al. |
6091411 |
July 2000 |
Straub et al. |
6092101 |
July 2000 |
Birrell et al. |
6094625 |
July 2000 |
Ralston |
6098065 |
August 2000 |
Skillen et al. |
6105063 |
August 2000 |
Hayes, Jr. |
6108197 |
August 2000 |
Janik |
6108665 |
August 2000 |
Bair et al. |
6112246 |
August 2000 |
Horbal et al. |
6122348 |
September 2000 |
French-St. George et al. |
6122657 |
September 2000 |
Hoffman, Jr. et al. |
6122960 |
September 2000 |
Hutchings et al. |
6127990 |
October 2000 |
Zwern |
6128663 |
October 2000 |
Thomas |
6131067 |
October 2000 |
Girerd et al. |
6134532 |
October 2000 |
Lazarus et al. |
6154745 |
November 2000 |
Kari et al. |
6155960 |
December 2000 |
Roberts et al. |
6164541 |
December 2000 |
Dougherty et al. |
6169976 |
January 2001 |
Colosso |
6185534 |
February 2001 |
Breese et al. |
6188399 |
February 2001 |
Voas et al. |
6195622 |
February 2001 |
Altschuler et al. |
6198394 |
March 2001 |
Jacobsen et al. |
6199099 |
March 2001 |
Gershman et al. |
6199102 |
March 2001 |
Cobb |
6215405 |
April 2001 |
Handley et al. |
6218958 |
April 2001 |
Eichstaedt et al. |
6230111 |
May 2001 |
Mizokawa |
6236768 |
May 2001 |
Rhodes et al. |
6256633 |
July 2001 |
Dharap |
6262720 |
July 2001 |
Jeffrey et al. |
6263268 |
July 2001 |
Nathanson |
6263317 |
July 2001 |
Sharp et al. |
6272470 |
August 2001 |
Teshima |
6272507 |
August 2001 |
Pirolli et al. |
6282517 |
August 2001 |
Wolfe et al. |
6285757 |
September 2001 |
Carroll et al. |
6285889 |
September 2001 |
Nykanen et al. |
6289316 |
September 2001 |
Aghili et al. |
6289513 |
September 2001 |
Bentwich |
6292796 |
September 2001 |
Drucker et al. |
6294953 |
September 2001 |
Steeves |
6301609 |
October 2001 |
Aravamudan et al. |
6305007 |
October 2001 |
Mintz |
6305221 |
October 2001 |
Hutchings |
6308203 |
October 2001 |
Itabashi et al. |
6311162 |
October 2001 |
Reichwein et al. |
6314384 |
November 2001 |
Goetz |
6317718 |
November 2001 |
Fano |
6321158 |
November 2001 |
DeLorme et al. |
6321279 |
November 2001 |
Bonola |
6324569 |
November 2001 |
Ogilvie et al. |
6327535 |
December 2001 |
Evans et al. |
6349307 |
February 2002 |
Chen |
6353398 |
March 2002 |
Amin et al. |
6353823 |
March 2002 |
Kumar |
6356905 |
March 2002 |
Gershman et al. |
6363377 |
March 2002 |
Kravets et al. |
6385589 |
May 2002 |
Trusheim et al. |
6392670 |
May 2002 |
Takeuchi et al. |
6401085 |
June 2002 |
Gershman et al. |
6405159 |
June 2002 |
Bushey et al. |
6405206 |
June 2002 |
Kayahara |
6418424 |
July 2002 |
Hoffberg et al. |
6421700 |
July 2002 |
Holmes et al. |
6427142 |
July 2002 |
Zachary et al. |
6430531 |
August 2002 |
Polish |
6438618 |
August 2002 |
Lortz et al. |
6442549 |
August 2002 |
Schneider |
6442589 |
August 2002 |
Takahashi et al. |
6442620 |
August 2002 |
Thatte et al. |
6446076 |
September 2002 |
Burkey et al. |
6446109 |
September 2002 |
Gupta |
6460036 |
October 2002 |
Herz |
6462759 |
October 2002 |
Kurtzberg et al. |
6466232 |
October 2002 |
Newell et al. |
6477117 |
November 2002 |
Narayanaswami et al. |
6483485 |
November 2002 |
Huang et al. |
6484200 |
November 2002 |
Angal et al. |
6487552 |
November 2002 |
Lei et al. |
6490579 |
December 2002 |
Gao et al. |
6505196 |
January 2003 |
Drucker et al. |
6507567 |
January 2003 |
Willars |
6507845 |
January 2003 |
Cohen et al. |
6513046 |
January 2003 |
Abbott et al. |
6519552 |
February 2003 |
Sampath et al. |
6526035 |
February 2003 |
Atarius et al. |
6529723 |
March 2003 |
Bentley |
6539336 |
March 2003 |
Vock et al. |
6542889 |
April 2003 |
Aggarwal et al. |
6546425 |
April 2003 |
Hanson et al. |
6546554 |
April 2003 |
Schmidt et al. |
6549915 |
April 2003 |
Abbott et al. |
6549944 |
April 2003 |
Weinberg et al. |
6553336 |
April 2003 |
Johnson et al. |
6563430 |
May 2003 |
Kemink et al. |
6568595 |
May 2003 |
Russell et al. |
6571279 |
May 2003 |
Herz et al. |
6578019 |
June 2003 |
Suda et al. |
6615197 |
September 2003 |
Chai |
6625135 |
September 2003 |
Johnson et al. |
6636831 |
October 2003 |
Profit et al. |
6643684 |
November 2003 |
Malkin et al. |
6652283 |
November 2003 |
Van Schaack et al. |
6661437 |
December 2003 |
Miller et al. |
6672506 |
January 2004 |
Swartz et al. |
6697836 |
February 2004 |
Kawano et al. |
6704722 |
March 2004 |
Wang Baldonado |
6704785 |
March 2004 |
Koo et al. |
6704812 |
March 2004 |
Bakke et al. |
6707476 |
March 2004 |
Hochstedler |
6712615 |
March 2004 |
Martin |
6714977 |
March 2004 |
Fowler et al. |
6738040 |
May 2004 |
Jahn et al. |
6738759 |
May 2004 |
Wheeler et al. |
6741188 |
May 2004 |
Miller et al. |
6741610 |
May 2004 |
Volftsun et al. |
6747675 |
June 2004 |
Abbott et al. |
6751620 |
June 2004 |
Orbanes et al. |
6766245 |
July 2004 |
Padmanabhan |
D494584 |
August 2004 |
Schlieffers et al. |
6791580 |
September 2004 |
Abbott et al. |
6795806 |
September 2004 |
Lewis et al. |
6796505 |
September 2004 |
Pellaumail et al. |
6801223 |
October 2004 |
Abbott et al. |
6812937 |
November 2004 |
Abbott et al. |
6829639 |
December 2004 |
Lawson et al. |
6834195 |
December 2004 |
Brandenberg et al. |
6834208 |
December 2004 |
Gonzales et al. |
6837436 |
January 2005 |
Swartz et al. |
6842877 |
January 2005 |
Robarts et al. |
6853966 |
February 2005 |
Bushey et al. |
6868525 |
March 2005 |
Szabo |
6874017 |
March 2005 |
Inoue et al. |
6874127 |
March 2005 |
Newell et al. |
6885734 |
April 2005 |
Eberle et al. |
6899539 |
May 2005 |
Stallman et al. |
6963899 |
November 2005 |
Fernandez et al. |
6968333 |
November 2005 |
Abbott et al. |
7000187 |
February 2006 |
Messinger et al. |
7010501 |
March 2006 |
Roslak et al. |
7010603 |
March 2006 |
Martin, Jr. et al. |
7040541 |
May 2006 |
Swartz et al. |
7046263 |
May 2006 |
Abbott et al. |
7055101 |
May 2006 |
Abbott et al. |
7058893 |
June 2006 |
Abbott et al. |
7058894 |
June 2006 |
Abbott et al. |
7062715 |
June 2006 |
Abbott et al. |
7063263 |
June 2006 |
Swartz et al. |
7076737 |
July 2006 |
Abbott et al. |
7080322 |
July 2006 |
Abbott et al. |
7089497 |
August 2006 |
Abbott et al. |
7096253 |
August 2006 |
Vinson et al. |
7103806 |
September 2006 |
Horvitz |
7107539 |
September 2006 |
Abbott et al. |
7110764 |
September 2006 |
Blair et al. |
7120558 |
October 2006 |
McIntyre et al. |
7124125 |
October 2006 |
Cook et al. |
7137069 |
November 2006 |
Abbott et al. |
7155456 |
December 2006 |
Abbott, III et al. |
7162473 |
January 2007 |
Dumais et al. |
7171378 |
January 2007 |
Petrovich et al. |
7195157 |
March 2007 |
Swartz et al. |
7203906 |
April 2007 |
Abbott et al. |
7225229 |
May 2007 |
Abbott et al. |
7231439 |
June 2007 |
Abbott et al. |
7260453 |
August 2007 |
Poier et al. |
7349894 |
March 2008 |
Barth et al. |
7360152 |
April 2008 |
Capps et al. |
7385501 |
June 2008 |
Miller et al. |
7386477 |
June 2008 |
Fano |
7392486 |
June 2008 |
Gyde et al. |
7395221 |
July 2008 |
Doss et al. |
7444594 |
October 2008 |
Abbott et al. |
7464153 |
December 2008 |
Abbott et al. |
7512889 |
March 2009 |
Newell et al. |
7533052 |
May 2009 |
Tilfors et al. |
7533082 |
May 2009 |
Abbott et al. |
7561200 |
July 2009 |
Garvey, III et al. |
7571218 |
August 2009 |
Tanaka et al. |
7614001 |
November 2009 |
Abbott et al. |
7647400 |
January 2010 |
Abbott et al. |
7689919 |
March 2010 |
Abbott et al. |
7734780 |
June 2010 |
Abbott et al. |
7739607 |
June 2010 |
Abbott et al. |
7779015 |
August 2010 |
Abbott et al. |
7827281 |
November 2010 |
Abbott et al. |
2001/0030664 |
October 2001 |
Shulman et al. |
2001/0040590 |
November 2001 |
Abbott et al. |
2001/0040591 |
November 2001 |
Abbott et al. |
2001/0043231 |
November 2001 |
Abbott et al. |
2001/0043232 |
November 2001 |
Abbott et al. |
2002/0032689 |
March 2002 |
Abbott, III et al. |
2002/0044152 |
April 2002 |
Abbott, III et al. |
2002/0052930 |
May 2002 |
Abbott et al. |
2002/0052963 |
May 2002 |
Abbott et al. |
2002/0054130 |
May 2002 |
Abbott, III et al. |
2002/0054174 |
May 2002 |
Abbott et al. |
2002/0078204 |
June 2002 |
Newell et al. |
2002/0080155 |
June 2002 |
Abbott et al. |
2002/0080156 |
June 2002 |
Abbott et al. |
2002/0083025 |
June 2002 |
Robarts et al. |
2002/0083158 |
June 2002 |
Abbott et al. |
2002/0087525 |
July 2002 |
Abbott et al. |
2002/0099817 |
July 2002 |
Abbott et al. |
2002/0147880 |
October 2002 |
Wang et al. |
2002/0191034 |
December 2002 |
Sowizral et al. |
2003/0046401 |
March 2003 |
Abbott et al. |
2003/0154476 |
August 2003 |
Abbott, III et al. |
2003/0186201 |
October 2003 |
Martin |
2003/0229900 |
December 2003 |
Reisman |
2004/0088328 |
May 2004 |
Cook et al. |
2004/0133600 |
July 2004 |
Homer |
2004/0186854 |
September 2004 |
Choi |
2004/0201500 |
October 2004 |
Miller et al. |
2004/0215663 |
October 2004 |
Liu et al. |
2004/0267700 |
December 2004 |
Dumais et al. |
2004/0267812 |
December 2004 |
Harris et al. |
2005/0027704 |
February 2005 |
Hammond et al. |
2005/0034078 |
February 2005 |
Abbott et al. |
2005/0066282 |
March 2005 |
Abbott et al. |
2005/0086243 |
April 2005 |
Abbott et al. |
2005/0160113 |
July 2005 |
Sipusic et al. |
2005/0165843 |
July 2005 |
Capps et al. |
2005/0193017 |
September 2005 |
Kim |
2005/0266858 |
December 2005 |
Miller et al. |
2005/0272442 |
December 2005 |
Miller et al. |
2006/0004680 |
January 2006 |
Robarts et al. |
2006/0019676 |
January 2006 |
Miller et al. |
2006/0136393 |
June 2006 |
Abbott et al. |
2006/0259494 |
November 2006 |
Watson et al. |
2007/0022384 |
January 2007 |
Abbott et al. |
2007/0043459 |
February 2007 |
Abbott et al. |
2007/0089067 |
April 2007 |
Abbott et al. |
2007/0130524 |
June 2007 |
Abbott et al. |
2007/0168502 |
July 2007 |
Abbott et al. |
2007/0185864 |
August 2007 |
Budzik et al. |
2007/0266318 |
November 2007 |
Abbott et al. |
2008/0090591 |
April 2008 |
Miller et al. |
2008/0091537 |
April 2008 |
Miller et al. |
2008/0147775 |
June 2008 |
Abbott et al. |
2008/0161018 |
July 2008 |
Miller et al. |
2008/0313271 |
December 2008 |
Abbott et al. |
2009/0013052 |
January 2009 |
Robarts et al. |
2009/0055752 |
February 2009 |
Abbott et al. |
2009/0150535 |
June 2009 |
Abbott et al. |
2009/0228552 |
September 2009 |
Abbott et al. |
2009/0234878 |
September 2009 |
Herz et al. |
2009/0282030 |
November 2009 |
Abbott et al. |
2010/0217862 |
August 2010 |
Abbott et al. |
2010/0257235 |
October 2010 |
Abbott et al. |
2010/0262573 |
October 2010 |
Abbott et al. |
|
Foreign Patent Documents
|
|
|
|
|
|
|
0661627 |
|
Jul 1995 |
|
EP |
|
0759591 |
|
Feb 1997 |
|
EP |
|
0801342 |
|
Oct 1997 |
|
EP |
|
0 823 813 |
|
Feb 1998 |
|
EP |
|
0846440 |
|
Jun 1998 |
|
EP |
|
0 924 615 |
|
Jun 1999 |
|
EP |
|
05260188 |
|
Oct 1993 |
|
JP |
|
0 9091112 |
|
Apr 1997 |
|
JP |
|
11306002 |
|
Nov 1999 |
|
JP |
|
WO 90/08361 |
|
Jul 1990 |
|
WO |
|
WO95/31773 |
|
Nov 1995 |
|
WO |
|
WO 97 03434 |
|
Jan 1997 |
|
WO |
|
WO97/34388 |
|
Sep 1997 |
|
WO |
|
WO9800787 |
|
Jan 1998 |
|
WO |
|
WO 98/47084 |
|
Oct 1998 |
|
WO |
|
WO 99/17228 |
|
Apr 1999 |
|
WO |
|
WO 99/26180 |
|
May 1999 |
|
WO |
|
WO99/66394 |
|
Dec 1999 |
|
WO |
|
WO 99/67698 |
|
Dec 1999 |
|
WO |
|
WO-0036493 |
|
Jun 2000 |
|
WO |
|
Other References
Affective Understanding: Modeling and Responding to User Affect.
Http://www.media.mit.edu/affect/AC.sub.--research/understanding.html.
Last accessed Oct. 2, 1998, pp. 1-3. cited by other .
Alps GlidePoint. Http://www.alps.com/p17.html. Last accessed Feb.
10, 1998, p. 1. cited by other .
Amon, et al. "Integration of Design Education, Research and
Practice at Carnegie Mellon University: A Multi-Disciplinary Course
in Wearable Computer Design," Proceedings of the Frontiers in
Education Conference, Nov. 1-4, 1995, pp. 4a1.14-4a1.22, vol. 2.
cited by other .
Aoki, et al. Realtime Personal Positioning System for a Wearable
Computer. Third International Symposium on Wearable Computers, San
Francisco, California, Oct. 18-19, 1999. cited by other .
Bacon, et al. "Using Events to Build Distributed Applications,"
University of Cambridge, 1996.
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.34.4545.
Last accessed Dec. 9, 2008, 8 pages. cited by other .
Bauer, et al. A Collaborative Wearable System with Remote Sensing.
University of Oregon, Feb. 1996. cited by other .
Bier, et al. "Toolglass and Magic Lenses: The See-Through
Interface," Proceedings of SIGGRAPH'93, Computer Graphics and
Annual Conference Series, ACM, pp. 73-80, Anaheim, California,
1993.
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.36.9741.
Last accessed Dec. 9, 2008, 8 pages. cited by other .
Billinghurst, et al. Wearable Devices: New Ways to Manage
Information, IEEE Computer Society, Jan. 1999, pp. 57-64. cited by
other .
Bishop. "Hard Ware," Jul. 28, 2000, Puget Sound Business Journal,
print edition, pp. 1-4. cited by other .
Biskup, et al. "Towards Secure Mediation." Oct. 1998. cited by
other .
Bowskill, et al. Wearable Location Mediated Telecommunications: A
First Step Towards Contexual Communication. Third International
Symposium on Wearable Computers, Oct. 18-19, 1999, San Francisco,
California. cited by other .
"BridgeVIEW and LabVIEW G Programming Reference Manual," Jan. 1998,
Nathional Instruments Corporation.
http://www.ni.com/pdf/manuals/321296b.pdf. Last accessed Dec. 7,
2008, 667 pages. cited by other .
Brown, et al. "Using Explicit Requirement and Metrics for Interface
Agent User Model Correction." Autonomous Agents '98. cited by other
.
Brown, et al. "Utility Theory-Based User Models for Intelligent
Interface Agents," Proceedings of the Twelfth Canadian Conference
on Artificial Intelligence (AI'98), Jun. 1998. cited by other .
Billinghurst, et al., An Evaluation of Wearable Information Spaces,
Proceedings of the Virtual Reality Annual International Symposium,
1998, 8 pages. cited by other .
Billinghurst. Research Directions in Wearable Computing, University
of Washington, May 1998, 48 pages. cited by other .
Budzik, et al. "Watson: Anticipating and Contextualizing
Information Needs," May 1, 1999, Proceedings of the 62nd Annual
Meeting of the American Society for Information Science, pp. 1-14.
cited by other .
"""Context-Awareness in Wearable and Ubiquitous Computing."" Future
Computing Environments, 1997. GVU Technical Report GIT-GVU-97-11.
http://www.cc.gatech.edu/fce/pubs/iswc97/wear.html. Last accessed
Dec. 8, 2008, 13 pages." cited by other .
"Context Recognition by User Situation Data Analysis (Context)."
http://www.cs.helsinki.fi/group/context/. Last accessed Dec. 9,
2008, 7 pages. cited by other .
Crabtree, et al. "Wearable Computing and the Remembrance Agent," BT
Technology Journal, vol. 16, No. 3, Jul. 1998, pp. 118-124.
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.31.8514.
Last accessed Dec 9, 2008, 7 pages. cited by other .
Dey, et al. The Conference Assistant Combining Context Awareness
with Wearable Computing. Third International Symposium on Wearable
Computers, Oct. 18-19, 1999, San Francisco, California. cited by
other .
D'Orazio, et al. Mobile Robot Position Determination Using Visual
Landmarks. IEEE Transactions on Industrial Electronics, vol. 41,
issue 6, Dec. 1994, pp. 654-662. Last accessed Dec. 9, 2008, 9
pages. cited by other .
Doorenbos, et al. "A Scalable Comparison-Shopping Agent for the
Worl-Wide-Web," Proceedings of the First International Conference
on Autonomous Agents, Marina Del Rey, California, Feb. 5-8, 1997,
pp. 39-48.
http://www.cs.washington.edu/homes/etzioni/papers/agents97.pdf.
Last accessed Dec. 9, 2008, 10 pages. cited by other .
Horvitz, et al., In Pursuit of Effective Handsfree Decision
Support: Coupling Bayesian Inference, Speech Understanding, and
User Models, 1995, 8 pages. cited by other .
Horvitz, et al., Attention-Sensitive Alerting in Computing Systems,
Microsoft Research, Aug. 1999. cited by other .
Fickas, et al. Software Organization for Dynamic and Adaptable
Wearable Systems. 1997. cited by other .
Finger, et al. Rapid Design and Manufacture of Wearable Computers.
Communication of the ACM, vol. 39, No. 2, Feb. 1996, pp. 63-68.
cited by other .
Gabbard, et al. A Taxonomy of Usability Characteristics in Virtual
Environments. 1997. cited by other .
Gavrilova. An Approach to Mapping of User Model to Corresponding
Interface Parameters. 1997. cited by other .
Goh, et al. "Context Interchange: New Features and Formalisms for
the Intelligent Integration of Information," ACM Transactions on
Information Systems, 1997.
http://dspace.mit.edu/bitstream/handle/1721.1/2642/SWP-3941-36987967.pdf?-
sequence=1. Last accessed Dec. 10, 2008, 25 pages. cited by other
.
Golding, et al. Indoor Navigation Using a Diverse Set of Cheap,
Wearable Sensors. Third International Symposium on Wearable
Computers, Oct. 18-19, 1999, San Francisco, California. cited by
other .
Goodridge. "The Environment Understanding Interface: Detecting and
Tracking Human Activity Through Multimedia Sensors." 1995. cited by
other .
Chen, et al., A Survey of Context-Aware Mobile Computing Research,
Dartmouth Computer Science Technical Report, 2000, 16 pages. cited
by other .
GyroPoint Technology. http://www.gyration.com/html/gyropoint.html.
Last accessed Oct. 2, 1998, pp. 1-3. cited by other .
Han, et al. "DBMiner: A System for Mining Knowledge in Large
Relational Databases," Proceedings 1996 International Conference on
Data Mining and Knowledge Discovery, Portland, OR, Aug. 1996.
http://www.cs.ualberta.ca/.about.zaiane/postscript/kdd96.pdf. Last
accessed Dec. 9, 2008, 6 pages. cited by examiner .
Haptics.
http://www.ai.mit.edu/projects/handarm-haptics/haptics.html. Last
accessed Feb. 10, 1998, pp. 1-2. cited by other .
Harter, et al. "A Distributed Location System for the Active
Office." IEEE Network, 1994, pp. 62-70. cited by other .
Hull, et al. Towards Situated Computing. Hewlette-Packard
Laboratories, HPL-97-66 (1997). cited by other .
"Intelligent User Interface Prompt Level," IBM Technical Disclosure
Bulletin, IBM Corp., New York, vol. 35, No. 1A, Jun. 1992, pp.
25-26. cited by other .
International Search Report dated Sep. 29, 2003 for PCT Application
Serial No. 00/20685, 3 Pages. cited by other .
International Search Report PCT/US01/32543, Oct. 27, 2003, 3 pages.
cited by other .
International Search Report for PCT Application No. PCT/US01/10394,
mailed Jun. 13, 2002, 5 pages. cited by other .
Jakobovits. "Integrating Autonomous Heterogeneous Information
Sources." University of Washington, Technical Report,
UV-CSE-971205, Jul. 15, 1997, 29 pages. cited by other .
Kirsch. The Sentic Mouse: A Tool for Measuring Emotional Valence.
Http://www.media.mit.edu/affect/AC.sub.--research/projects/sentic.sub.--m-
ouse.html. Last accessed Feb. 19, 1998, pp. 1-2. cited by other
.
Kortuem, et al. Context Aware, Adaptive, Wearable Computers as
Remote Interfaces to Intelligent Environments. University of
Oregon, Oct. 1998, 8 pages. cited by other .
Kortuem. When Cyborgs Meet: Building Communities of Cooperating
Wearable Agents. Third International Symposium on Wearable
Computers, Oct. 18-19, 1999, San Francisco, California. cited by
other .
"LabVIEW User Manual," Jan. 1998 Edition, National Instruments.
http://claymore.engineergvsu.edu/eod/courses/egr450/media/320999b.pdf.
Last accessed Dec. 7, 2008, 514 pages. cited by other .
Lashkari, et al. Collaborative Interface Agents. Proceedings of
AAAI'94 Conference, Seattle, Washington, Aug. 1994. cited by other
.
Lehikoinen, et al. MEX: A Distributed Software Architecture for
Wearable Computers. Third International Symposium on Wearable
Computers, Oct. 18-19, 1999, San Francisco, California. cited by
other .
Leonhardi, et al. Virtual Information Towers--A Metaphor Intuitive,
Location-Aware Information Access in a Mobile Environment. Third
International Symposium on Wearable Computers, Oct. 18-19, 1999,
San Francisco, California. cited by other .
Leonhardt, et al. "Multi-Sensor Location Tracking." Department of
Computing, London, UK, Oct. 1998. cited by other .
Losee, JR. Minimizing information overload: the ranking of
electronic messages, Journal of Information Science 15, Elsevier
Science Publishers B.V., 1989, pp. 179-189. cited by other .
Lunt, et al. Knowledge-Based Intrusion Detection. Proceedings of
the Annual Artificial Intelligence Systems in Government
Conference, IEEE Comp. Soc. Press, vol. Conf.4, 1989, pp. 102-107.
cited by other .
Maes. Agents That Reduce Work and Information Overload.
Communications of the ACM, vol. 37, No. 7, Jul. 1994. cited by
other .
Mann. Smart Clothing: Wearable Multimedia Computing and Personal
Imaging to Restore the Technological Balance Between People and
Their Environments. ACM Multimedia, Nov. 1996, pp. 163-174. cited
by other .
Metz. MIT: Wearable PCs, Electronic Ink and Smart Rooms. PC
Magazaine, pp. 192-193, Jun. 1998. cited by other .
Mott, et al. "A Formalism for Context Mediation Based on Feature
Logic." Feb. 1998.
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.52.4473.
Last accessed Dec. 10, 2008, 11 pages. cited by other .
Ni. "Attribute Name Evaluation and Its Implementation," School of
Computing and Mathematics, Deakin University, Geelong, Victoria,
May 16, 1994.
http://www.deakin.edu.au/scitech/sit/dsapp/archive/techreport/TR-C9-
4-10.pdf. Last accessed Dec. 9, 2008, 32 pages. cited by other
.
OA Dated Oct. 30, 2008 for U.S. Appl. No. 11/490,540, 37 pages.
cited by other .
OA Dated Sep. 15, 2008 for U.S. Appl. No. 11/033,974, 17 pages.
cited by other .
OA Dated Aug. 14, 2008 for U.S. Appl. No. 10/981,941, 14 pages.
cited by other .
OA Dated Dec. 3, 2008 for U.S. Appl. No. 09/981,320, 40 pages.
cited by other .
OA Dated Aug. 1, 2008 for U.S. Appl. No. 11/179,822, 17 pages.
cited by other .
OA Dated Sep. 17, 2008 for U.S. Appl. No. 09/894,642, 28 pages.
cited by other .
OA Dated Jul. 29, 2008 for U.S. Appl. No. 10/984,511, 28 pages.
cited by other .
OA Dated Dec. 4, 2008 for U.S. Appl. No. 11/567,902, 21 pages.
cited by other .
OA Dated Nov. 28, 2008 for U.S. Appl. No. 11/761,210, 11 pages.
cited by other .
Oakes. The Truman Show Realized?
http://www.wired.com/news/news/technology/story/15745.html. Last
accessed Feb. 10, 1998, pp. 1-4. cited by other .
Ockerman, et al. "Wearable Computer for Performance Support:
Initial Feasibility Study," International Symposium in Wearable
Computers, Oct. 1997, pp. 10-17. cited by other .
Papakonstantinou, et al. "MedMaker: A Mediation System Based on
Declarative Specifications." 1995.
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.35.735.
Last accessed Nov. 25, 2008, 10 pages. cited by other .
Picard, et al. Affective Wearables. Personal Technologies vol. 1,
231-240, MIT Media Laboratory (1997). cited by other .
Rekimoto, et al. The World Through the Computer: Computer Augmented
Interaction with Real World Environments, ACM, Nov. 1995, pp.
29-36. cited by other .
Research Areas in Affective Computing.
Http://www.media.mit.edu/affect/. Last accessed Feb. 10, 1998, p.
1. cited by other .
Research on Affective Pattern Recognition and Modeling.
Http://www.media.mit.edu/affect/AC.sub.--research/recognizing.html.
Last accessed Feb. 10, 1998, pp. 1-4. cited by other .
Research on Sensing Human Affect.
Http://www.media.mit.edulaffect/AC.sub.--research/sensing.html.
Last accessed Feb. 10, 1998, pp. 1-5. cited by other .
Rhodes, Remembrance Agent: A continuously running automated
information retrieval system, The Proceedings of the First
International Conference on the Practical Application of
Intelligent Agents and Multi Agent Technology, 1996, pp. 487-495.
cited by other .
Rhodes, The Wearable Remembrance Agent: A System for Augmented
Memory, Personal Technologies Journal Special Issue on Wearable
Computing, 1997, 12 pages. cited by other .
Rhodes. The Wearable Rememberance Agent: A System for Augmented
Memory. Proceedings of the First International Symposium on
Wearable Computers (ISWC'97), Cambridge, MA, Oct. 13-14, 1997.
cited by other .
Rhodes. WIMP Interface Considered Fatal.
http://rhodes.www.media.mit.edu/people/rhodes/Papers/no-wimp.html.
Last accessed Feb. 10, 1998, pp. 1-3. cited by other .
Rogers, et al. Outbreak Agent: Intelligent Wearable Technology for
Hazardous Environments. IEEE International Conference, Orlando,
Florida, Oct. 12-15, 1997, pp. 3198-3203.
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.46.8827.
Last accessed Nov. 25, 2008, 6 pages. cited by other .
Rosis, et al. "Adaptive Interaction with Knowledge-Based System,"
ACM 1994. cited by other .
Sato, et al. Autonomous Behaviour Control of Virtual Actors Based
on the AIR Model. Proceedings Computer Animation, Jun. 5, 1997.
cited by other .
Schilt. A System Architecture for Context-Aware Mobile Computing,
Columbia University, 1995, 153 pages. cited by other .
Schilit, et al., The ParcTab Mobile Computing System, IEEE WWOS-IV,
1993, 4 pages. cited by other .
Schilit, et al., Context-Aware Computing Applications, In
Proceedings of the Workshop on Mobile Computing Systems and
Applications, Dec. 1994. pp. 85-90. cited by other .
Schilit, et al., Customizing Mobile Applications, Proceedings
USENIX Symposium on Mobile and Location Independent Computing, Aug.
1993, 9 pages. cited by other .
Schilit, et al., Disseminating Active Map Information to Mobile
Hosts, IEEE Network, 1994, pp. 22-32, vol. 8--No. 5. cited by other
.
Schmidt, et al. "There's More to Context Than Location."
Proceedings of the International Workshop on Interactive
Applications of Mobile Computing (IMC98), Germany, Nov. 1998, 10
pages.
http://citeseer.comp.nus.edu.sg/cache/papers/cs/16114/http:zSzzSzwww.teco-
.eduzSz.about.albrechtzSzpublicationzSzdraft.sub.--docszSzcontext-is-more--
than-location.pdf/there-is-more-to.pdf. cited by other .
Schneider, et al. Modeling Wearable Negotiation in an Opportunistic
Task Oriented Domain. Third International Symposium on Wearable
Computers, Oct. 18-19, 1999, San Francisco, California. cited by
other .
Smailagic, et al. Matching Interface Design with User Task:
Modalities of Interaction with CMU Wearable Computers. IEEE
Personal Communications, Feb. 1996, pp. 14-25. cited by other .
Smailagic, et al. MoCCA: A Mobile Communication and Computing
Architecture. Third International Symposium on Wearable Computers,
Oct. 18-19, 1999, San Francisco, California. cited by other .
Smart Rooms.
http://vismod.www.media.mit.edu/vismod/demos/smartroom/. Last
accessed Feb. 10, 1998, pp. 1-3. cited by other .
SmartDesk Home Page.
http://vismod.www.media.mit.edu/vismod/demos/smartdesk/. Last
accessed Feb. 10, 1998, pp. 1-4. cited by other .
Spreitzer, et al. "Providing Location Information in a Ubiquitous
Computing Environment," Xerox Palo Alto Research Center , ACM,
1993, pp. 270-283.
http://www.comp.lancs.ac.uk/computing/staff/kc/Lecturing/MSc/wk1-
0/p270-spreitzer.pdf. Last accessed Dec. 9, 2008, 14 pages. cited
by other .
Spreitzer, et al. Architectural Considerations for Scalable,
Secure, Mobile Computing with Location Information, In the 14th
International Conference on Distributed Computing Systems, Jun.
1994, pp. 29-38. cited by other .
Spreitzer et al. Scalable, Secure, Mobile Computing with Location
Information, Communications of the ACM, Jul. 1993, 1 page, vol.
36--No. 7. cited by other .
Starner, et al. Visual Contexual Awareness in Wearable Computing.
Media Lab, MIT, Oct. 1998. cited by other .
Starner. Wearable Computing and Contextual Awareness, Massachusetts
Institute of Technology, Jun. 1999, 248 pages. cited by other .
T. Joachims, Text categorization with support vector machines:
learning with many relevant features, Machine Learning, European
Conference on Machine Learning, Apr. 21, 1998, pp. 137-142. cited
by other .
Tan, et al. Tactual Displays for Wearable Computing, IEEE, MIT
Media Laboratory, pp. 84-88, 1997. cited by other .
The MIT Wearable Computing Web Page.
http://wearable.www.media.mit.edu/projects/wearables/. Last
accessed Feb. 10, 1998, pp. 1-3. cited by other .
Theimer, et al. Operating System Issues for PDAs, In Fourth
Workshop on Workstation Operating Systems, 1993, 7 pages. cited by
other .
Wachowicz, et al. "Combining Location and Data Management in an
Environment for Total Mobility," University of Cambridge, England,
1996.
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.37.4550.
Last accessed Dec. 9, 2008, 12 pages. cited by other .
Want, Active Badges and Personal Interactive Computing Objects,
IEEE Transactions on Consumer Electronics, 1992, 11 pages, vol.
38--No. 1. cited by other .
Want, et al., The Active Badge Location System, ACM Transactions on
Information Systems, Jan. 1992, pp. 91-102, vol. 10--No. 1. cited
by other .
Wardell. "Stardock.net Releases WindowBlinds." Stardock.net, Inc.
Oct. 4, 1999, http://stardock.net/media/pr.sub.--wb10.html. Last
accessed Dec. 9, 2008, 2 pages. cited by other .
Wearable Computer Systems for Affective Computing.
http://www.media.mit.edu/affect/AC.sub.--research/wearables.html.
Last accessed Feb. 10, 1998, pp. 1-5. cited by other .
Weiser. The Computer for the 21st Century, Scientific American,
Sep. 1991, 8 pages. cited by other .
Weiser. Some Computer Science Issues in Ubiquitous Computing,
Communications of the ACM, Jul. 1993, pp. 75-84, vol. 36--No. 7.
cited by other .
Workshop on Wearable Computing Systems, Aug. 19-21, 1996. cited by
other .
Yang. SmartSight: A Tourist Assistant System. Third International
Symposium on Wearable Computers, Oct. 18-19, 1999, San Francisco,
California. cited by other .
Zenel, et al. "A General Purpose Proxy Filtering Mechanism Applied
to the Mobile Environment," Proceedings of the 3rd annual ACM/IEEE
international conference on Mobile computing and networking,
MOBICOM'97, Budapest, Hungary, pp. 248-259.
http://portal.acm.org/citation.cfm?id=262153. Last accessed Dec. 9,
2008, 12 pages. cited by other .
Bates et al., Middleware Support for Mobile Multimedia
Applications, ICL System Journal, Nov. 1997, 20 pages. cited by
other .
Cugola et al., Exploiting an Event-Based Infrastructure to Develop
Complex Distributed Systems, 20th International Conference on
Software Engineering (ICSE'98) Apr. 1998, p. 261-70, 10 pages.
cited by other .
Dechamboux et al., Using a Distributed Shared Memory for
Implementing Efficient Information Mediators, Proceedings of the
International Conference and Exhibition on High-Performance
Computing and Networking, Apr. 1996, 5 pages. cited by other .
Dey et al., CyberDesk: A Framework for Providing Self-Integrating
Context-Aware Services, Knowledge-Based Systems, 11:3-13, 1998, 10
pages. cited by other .
European Office Action dated Feb. 13, 2009 for EP Application No.
01964695.9, 4 pages. cited by other .
Goharian et al., Enterprise Text Processing: A Sparse Matrix
Approach, 2001, IEEE, pp. 71-75. cited by other .
International Search Report, Application No. PCT/US01/10599, Nov.
28, 2002. cited by other .
International Search Report, PCT/US01/10538, Aug. 14, 2002, 2
pages. cited by other .
OA dated Jan. 2, 2009 for U.S. Appl. No. 11/559,854, 23 pages.
cited by other .
Ockerbloom, Mediating Among Diverse Data Formats: Thesis Summary,
PhD Thesis, Technical Report CMU-CS-98-102, Department of Computer
Sciences, Carnegie Mellon University, Pittsburgh, PA, Jan. 14,
1998, 15 pages. cited by other .
Pascoe, Adding Generic Contextual Capabilities to Wearable
Computers, Proceedings of the 2nd International Symposium on
Wearable Computers (ISWC '98), Pittsburgh, PA, Oct. 19-20, 1998, 8
pages. cited by other .
Sawhney, Contextual awareness, messaging and communication in
nomadic audio environments, Massachusetts Institute of Technology,
Jun. 1998 pp. 80-105, 25 pages. cited by other .
Starovic, An Event Based Object Model for Distributed Programming,
Technical Report TCD-CS-95-28, Dept. of Computer Science, Trinity
College Dublin, Ireland, 1995, retrieved from
http://citeseer.ist.psu.edu/starovic95event.html, 15 pages. cited
by other .
Salber et al., The Design and Use of a Generic Context Server.
Technical Report GIT-GVU-98-32. GVU Center, College of Computing,
Georgia Institute of Technology. 1998. Available at
ftp://ftp.cc.gatech.edu/pub/gvu/tr/1998/98-32.pdf. Last accessed
Mar. 12, 2010. cited by other.
|
Primary Examiner: Hailu; Tadeese
Attorney, Agent or Firm: Wolf, Greenfield & Sacks,
P.C.
Parent Case Text
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. patent application Ser.
No. 11/075,529, filed Mar. 8, 2005, entitled "INTERFACE FOR
EXCHANGING CONTEXT DATA," now U.S. Pat. No. 7,478,331, which is a
continuation of U.S. patent application Ser. No. 09/692,507, filed
Oct. 19, 2000, entitled "INTERFACE FOR EXCHANGING CONTEXT DATA,"
now U.S. Pat. No. 6,920,616, which is a continuation-in-part of
U.S. patent application Ser. No. 09/541,328, filed Apr. 2, 2000,
entitled "INTERFACE FOR EXCHANGING CONTEXT DATA," now abandoned,
and of U.S. patent application Ser. No. 09/541,326, filed Apr. 2,
2000, entitled "LOGGING AND ANALYZING COMPUTER USER'S CONTEXT
DATA," now abandoned, and of U.S. patent application Ser. No.
09/216,193, filed Dec. 18, 1998, entitled "METHOD AND SYSTEM FOR
CONTROLLING PRESENTATION OF INFORMATION TO A USER BASED ON THE
USER'S CONDITION," now U.S. Pat. No. 6,466,232, all of which are
hereby incorporated by reference in their entirety.
Claims
We claim:
1. A method in a computing device for exchanging context attributes
through an application programming interface of a facility, the
method comprising: with at least one processor: receiving an
enumeration request through the application programming interface
for an enumeration of context attribute types; in response to
receiving the enumeration request, providing to a requesting
attribute consumer a list of context attribute types available from
the facility, each of the context attributes being identified by a
respective name; receiving an invocation request to provide an
attribute value, the invocation request being generated by the
requesting attribute consumer, the invocation request identifying
the type of the context attribute whose value is to be provided,
the context attribute type being in the list and being identified
in the invocation request by the respective name in the list; and
in response to receiving the invocation request, providing a value
for the identified attribute to the requesting attribute
consumer.
2. The method of claim 1 wherein the invocation request is a
function call or a procedure or an invocation message.
3. The method of claim 1 wherein a value of the identified
attribute is stored, and wherein the stored value is provided to
the requesting attribute consumer.
4. The method of claim 1 wherein the identified attribute is
associated with an attribute source, and wherein the method further
comprises obtaining a value of the identified attribute from the
attribute source with which the identified attribute is associated,
and wherein the value of the attribute obtained from the attribute
source with which the identified attribute is provided to the
requesting attribute consumer.
5. The method of claim 1 further comprising, in addition to
providing a value for the identified attribute to the requesting
attribute consumer, providing units of the value for the identified
attribute.
6. The method of claim 1 further comprising, in addition to
providing a value for the identified attribute to the requesting
attribute consumer, providing an uncertainty level for the
identified attribute.
7. The method of claim 1 further comprising, in addition to
providing a value for the identified attribute to the requesting
attribute consumer, providing a timestamp for the identified
attribute.
8. The method of claim 1 wherein the identified attribute is
information reflecting an aspect of the computing device, and
wherein the computing device has a visual output device, and
wherein the identified attribute is information about the
availability of the visual output device.
9. The method of claim 1 wherein the computing device is present in
an environment, wherein the environment has a temperature, and
wherein the identified attribute is the temperature of the
environment.
10. The method of claim 1 wherein the computing device has a user,
and wherein the identified attribute is information reflecting an
aspect of the user.
11. The method of claim 10 wherein the user has a blood pressure,
wherein the identified attribute is the blood pressure of the
user.
12. The method of claim 1 wherein one or more applications are
executing on the computing device, and wherein the identified
attribute is information reflecting an aspect of an executing
application.
13. The method of claim 12 wherein an electronic messaging
application is among the applications executing on the computing
device, and wherein the identified attribute indicates whether new
messages have been received by the electronic messaging
application.
14. The method of claim 1 wherein the computing device is outside a
selected remote environment, and wherein the identified attribute
is information reflecting an aspect of the remote environment.
15. The method of claim 14 wherein the environment has a
temperature, and wherein the identified attribute is the
temperature of the remote environment.
16. The method of claim 1 wherein the computing device has a user,
and wherein the identified attribute is information reflecting an
aspect of a selected person other than the user.
17. Computer-readable memory comprising computer-executable
instructions that, when executed by a processor, implement a
facility with an application programming interface, the method
comprising: receiving an enumeration request through the
application programming interface for an enumeration of context
attribute names; in response to receiving the enumeration request,
providing to a requesting attribute consumer a list of context
attribute names available from the facility; receiving an
invocation request to provide an attribute value, the invocation
request being generated by the requesting attribute consumer, the
invocation request identifying the name of the attribute whose
value is to be provided, the context attribute name being in the
list; and in response to receiving the invocation request,
providing a value for the identified attribute to the requesting
attribute consumer.
18. The computer-readable memory of claim 17, wherein: the
enumeration request comprises criteria; and the list of context
attributes comprises context attributes meeting the criteria.
19. The method of claim 1, wherein the attribute is derived.
20. The method of claim 1, wherein the attribute has at least three
properties selected from the group consisting of: a name, a value,
an uncertainty level, units, and a time stamp.
Description
TECHNICAL FIELD
The present invention is directed to the field of context modeling
and, more particularly, to the field of data exchange for context
modeling.
BACKGROUND
Wearable computers are devices that commonly serve as electronic
companions and intelligent assistants to their users. A wearable
computer is typically strapped to its user's body or carried by its
user in a holster, and can contain a variety of both input and
output devices. A wearable computer can output information to its
user using, for example, display eyeglasses, audio speakers, or a
tactile output device. A wearable computer can receive instructions
and other input from its user via input devices such as a keyboard,
various pointing devices, or an audio microphone. A wearable
computer can receive information about its surroundings using
sensors, such as barometric pressure and temperature sensors,
global positioning system devices, or a heart rate monitor for
determining the heart rate of its user and can receive additional
information via communication devices, such as various types of
network connections. A wearable computer can exchange information
with other devices using communication schemes such as infrared
communication, radio communication, or cellular modems.
Many applications for wearable computers utilize data received by
the wearable computer from sensors. For example, a position mapping
application for a wearable computer may utilize data received from
a global positioning system device to plot its user's physical
location and determine whether that position is within a special
region. In this example, the global positioning system device
produces data that is consumed by the position
mapping-application.
In conventional wearable computer systems, the position mapping
application would be designed to interact directly with the global
positioning system device to obtain the needed data. For example,
the application may be required to instruct the device to obtain
position information, retrieve the information obtained by the
device, convert it to conventional latitude and longitude
representation, and determine whether the represented location is
within the special region.
Such direct interaction between applications and sensors to obtain
and process data has significant disadvantages. First, developing
an application to interact directly with a particular sensor can
introduce into the application dependencies on that sensor.
Accordingly, the application may need to be subsequently modified
to interact successfully with alternatives to that sensor provided
by other manufacturers, or even to interact successfully with
future versions of the sensor from the same manufacturer.
Second, direct interaction between the application and the sensor
can give rise to conflicts between multiple applications that
consume the same data. For example, if the position mapping
application was executing on the same wearable computer as a second
application for determining the user's distance from home that also
used the global positioning system device, the two applications'
interactions with the device could interfere with one another.
Third, direct interaction between the application and the sensor
can give rise to conflicts between multiple sensors that produce
the same data. For example, if the position mapping application was
executing on a wearable computer that had access to both the global
positioning system device and an indoor positioning system, the
application might well have trouble determining which device to use
to determine the user's current position, and/or have trouble
reconciling data produced by both devices.
Fourth, performing the derivation of abstract information from data
observable by sensors in each application that requires the derived
abstract information necessitates redundant functionality in each
such application, and precludes the development of multiple
competing algorithms to derive the same abstract information;
rather than having to themselves process data from the sensor to
derive more abstract information from data observable by sensors,
it would be advantageous for applications to be able to rely on a
separate programmatic entity to derive such abstract information.
For example, it would be more convenient for the position mapping
application to be able rely on a separate programmatic entity to
determine whether the user is in a special region based upon the
user's location. It would further be advantageous for such
applications to share a single separate programmatic entity, rather
each implementing the same derivation functionality.
Accordingly, a facility for exchanging information between sensors
and applications in a wearable computer system would have
significant utility.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates an embodiment of the characterization module
which executes on a general-purpose body-mounted wearable computer
120 worn by a user 110.
FIG. 2 illustrates an exemplary computer system 200 on which an
embodiment of the characterization module is executing.
FIG. 3 is a data flow diagram showing a sample exchange of
attributes performed by the characterization module.
FIG. 4 is a data structure diagram showing a context server table
that maintains a portion of the state of the characterization
module.
FIG. 5 is a data structure diagram showing an attribute instance
table that maintains a portion of the state of the characterization
module.
FIG. 6 is a data structure diagram showing a context client table
that maintains a portion of the state of the characterization
module.
FIG. 7 is a data structure diagram showing an attribute or instance
registration table that maintains a portion of the state of the
characterization module.
FIG. 8 is a low diagram showing the steps preferably performed by
the characterization module when the GetAttribute function is
called.
FIG. 9 is a data structure diagram showing updated contents of the
attribute instance table.
FIG. 10 is a data structure diagram showing a condition table that
contains a portion of the state of the characterization module.
FIG. 11 is a data structure diagram showing a condition monitor
table that maintains a portion of the state of the characterization
module.
FIG. 12 is a data structure diagram showing updated contents of the
condition monitor table.
FIG. 13 is a data flow diagram showing the operation of the
facility without a characterization module.
FIG. 14 is a data structure diagram showing an attribute instance
property table that maintains a portion of the state of the
characterization module.
DETAILED DESCRIPTION
A software facility for exchanging information between sources of
context data and consumers of context data ("the facility") is
provided. In a preferred embodiment, a characterization module
operating in a wearable computer system receives context
information, in the form of individual attributes each modeling an
aspect of the wearable computer system, its user, or the
surrounding environment, from one or more context servers, and
provides it to one or more context clients. The facility reduces
dependencies of context client applications on specific sensors and
other input devices, reduces conflicts between context client
applications that consume the same context data, resolves conflicts
between multiple sensors or other input devices that produce the
same data, isolates the derivation of derived attributes from
context client applications, and therefore obviates the redundant
effort of implementing the derivation of derived attributes in each
context server, and facilitates the development and use of
competing algorithms to derive derived attributes.
Attributes represent measures of specific context elements such as
ambient temperature, location and current user task. Each attribute
preferably has the following properties: a name, a value, an
uncertainty level, units, and a time stamp. Attributes provided
through the characterization module by a context server may either
be "measured," in that they are directly received from an input
device, or "derived," in that they are the result of performing
processing on values directly obtained from input devices other
attributes. Indeed, a derived attribute may be produced by
performing additional processing on other derived attributes.
Context servers, in addition to providing attributes through the
characterization module, may also provide other functions. For
example, an application, such as an electronic mail application,
could serve as a context server by providing attributes through the
characterization module. In addition to the source of attributes
described above, such an "expanded" context server may provide
attributes relating to the other functions of the expanded context
server. For example, an electronic mail application context server
could provide an attribute indicating other new messages are
waiting. Indeed, the same program module may operate both as a
context client and a context server.
Two or more different context servers may preferably supply to the
characterization module their own values for a single attribute.
For example, a first context server can supply a value for a
user.location attribute based on data received from a global
positioning system device, while a second context server can supply
a value for the user.location attribute based on data received from
an indoor positioning device. These separate values for the same
attribute are referred to as separate "instances" of the attribute.
The characterization module preferably provides a variety of
different approaches, called "mediators," for determining, when an
attribute requested by a context client has more than one instance,
what attribute value to provide in response to the attribute
request.
When the characterization module obtains an attribute value from a
context server, it preferably caches it for responding to future
requests for the attribute from context clients. Such attribute
requests may specify a specific instance of the attribute--that is,
a specific context server from which the attribute is to be
obtained--or may specify that the attribute is to be obtained by
applying a particular mediator to whatever instances of the
attribute are available, or may utilize a default mediator to
mediate between available instances of the attribute. When the
characterization module receives an attribute request from a
context client, it identifies the attribute instances available to
satisfy the request, and, for each, determines whether the value
for the attribute instance cached by the characterization module
was obtained sufficiently recently from the corresponding context
server. If not, the characterization module requests an updated
value for the attribute instance from the corresponding context
server before performing any necessary mediation and returning a
value to the context client.
Context servers and context clients preferably interact with the
characterization module by calling functions provided by the
characterization module. These functions are said to collectively
comprise an "application programming interface" (or "API") to the
characterization module.
A context client that seeks to request a particular attribute or
attribute instance may call a LaunchContextServer function to
launch a particular context server that is not executing. Each
executing context server preferably registers with the
characterization module by calling a RegisterContextServer
function, identifying itself. The context server goes on to make an
instance of an attribute available to context clients via the
characterization module by following a CreateAttributeInstance
function. A particular context server may preferably provide a
number of different attributes by calling the
CreateAttributeInstance function multiple times. Before seeking to
consume an attribute, a context client calls a
RegisterContextClient function, identifying itself. In order to
consume an attribute, a context client calls a
RegisterToConsumeAttributeOrInstance function, identifying itself
and an attribute that it seeks to consume. To help determine which
attributes to consume, a context client may call a
EnumerateAttributes function to obtain a list of the attributes
available from the characterization module. In order to actually
retrieve an attribute value, a context client calls a GetAttribute
function, identifying the attribute and any attribute processing
that should be applied, such as a specific type of mediation
between different instances of the attribute obtained from
different context servers. For attributes that have multiple
instances in the characterization module, a context client may call
a GetAllAttributeInstances function to obtain a value of the
attribute for each attribute instance. To force a particular
context server to reevaluate all of its attribute instances, a
context client may call a CompleteContextServerEvaluation function.
Also, to retrieve attributes reflecting aspects of the
configuration of the characterization module, a context client or
other program may call a GetCharacterizationModuleAttribute
function. A context client that consumes a particular attribute may
create a condition in the characterization module that tests that
attribute by calling a CreateCondition function. Once a context
client has created a condition, it can evaluate the condition by
calling an EvaluateCondition function, identifying the condition.
Once a context client has created a condition, it may go on to call
a CreateConditionMonitor function to create a condition monitor
that monitors the condition and notifies the context server when
the condition is satisfied. To suspend operation of a created
condition monitor, a context server may call a StopConditionMonitor
function, and to resume its operation, may call a
StartConditionMonitor function. The context server may remove a
condition monitor that it created by calling a
RemoveConditionMonitor function, and, correspondingly, may remove a
condition that it created by calling a RemoveCondition function. A
context client may unregister to consume a particular attribute by
calling an UnregisterToConsumeAttributeOrInstance function. A
context client may unregister itself with the characterization
module by calling an UnregisterContextClient function. A context
server may--though need not--remove attribute instances that it has
registered by calling a RemoveAttributeInstance function. Before it
does, however, it may--though need not--first call a
CheckAttributeInstanceDependencies function to determine whether
any context clients currently depend upon that attribute instance.
Once it has removed its attribute instances, a context server may
unregister with the characterization module by calling an
UnregisterContextServer function. These API functions are discussed
in greater detail below in conjunction with an example.
FIG. 1 illustrates an embodiment of the characterization module
which executes on a general-purpose body-mounted wearable computer
120 worn by a user 110. Many wearable computers are designed to act
as constant companions and intelligent assistants to a user, and
are often strapped to a user's body or mounted in a holster. The
computer system may also be incorporated in the user's clothing, be
implanted in the user, follow the user, or otherwise remain in the
user's presence. In one preferred embodiment the user is human, but
in additional preferred embodiments, the user may be an animal, a
robot, a car, a bus, or another entity whose context data is to be
processed. Indeed, the computer system may have no identifiable
user, but rather operate as an independent probe, processing
context data in an arbitrary location. The wearable computer 120
has a variety of user-worn user input devices including a
microphone 124, a hand-held flat panel display 130 with character
recognition capabilities, and various other user input devices 122.
Similarly, the computer has a variety of user-worn output devices
that include the hand-held flat panel display, an earpiece speaker
132, an eyeglass-mounted display 134, and a tactile display 136. In
addition to the various user-worn user input devices, the computer
can also receive information from various user sensor input devices
116 and from environment sensor input devices 128, including video
camera 121. The characterization module can receive and process the
various input information received by the computer, such as from
context servers that process the input information and generate
attribute values, and can present information to the user on the
various output devices accessible to the computer.
In the current environment, computer 120 is accessible to a
computer 150 (e.g., by being in line-of-sight wireless proximity or
by being reachable via a long-distance communication device such as
a cellular phone) which also has a variety of input and output
devices. In the illustrated embodiment the computer 150 is
non-portable, although the body-mounted computer of the user can
similarly communicate with a variety of other types of computers,
including body-mounted computers of other users. The devices from
which the non-portable computer can directly receive information
include various user input devices 152 and various user sensor
input devices 156. The non-portable computer can output information
directly to a display 160, a speaker 162, an olfactory device 164,
and a printer 166. In the illustrated embodiment, the body-mounted
computer can communicate with the non-portable computer via a
wireless transmission medium. In this manner, the characterization
module can receive information from the user input devices 152 and
the user sensor devices 156 after the information has been
transmitted to the non-portable computer and then to the
body-mounted computer. Alternately, the body-mounted computer may
be able to directly communicate with the user input devices 152 and
the user sensor devices 156, as well as with other various remote
environment sensor input devices 158, without the intervention of
the non-portable computer 150. Similarly, the body-mounted computer
may be able to supply output information to the display 160, the
speaker 162, the olfactory device 164, and the printer 166, either
directly or via the non-portable computer, and directly to the
telephone 168. As the user moves out of range of the remote input
and output devices, the characterization module will be updated to
reflect that the remote devices are not currently available.
The various input devices allow the characterization module or an
application such as a context server (not shown) executing on the
computer system 120 to monitor the user and the environment and to
model their current condition. Such a model can be used by various
applications, such as context clients, for various purposes. A
model of the current conditions can include a variety of condition
variables that represent information about the user, the computer,
and the user's environment at varying levels of abstraction. For
example, information about the user at a low level of abstraction
can include raw physiological data (e.g., heart rate and EKG) and
geographic information (e.g., location and speed), while higher
levels of abstraction may attempt to characterize or predict the
user's physical activity (e.g., jogging or talking on a phone),
emotional state (e.g., angry or puzzled), desired output behavior
for different types of information (e.g., to present private family
information so that it is perceivable only to myself and my family
members), and cognitive load (i.e., the amount of attention
required for the user's current activities). Background information
which changes rarely or not at all can also be included, such as
the user's age, gender and visual acuity. The model can similarly
hold environment information at a low level of abstraction, such as
air temperature or raw data from a motion sensor, or at higher
levels of abstraction, such as the number and identities of nearby
people, objects, and locations. The model of the current conditions
can additionally include information added explicitly from other
sources (e.g., application programs), as well as user-specified or
system-learned defaults and preference information.
Those skilled in the art will appreciate that computer systems 120
and 150, as well as their various input and output devices, are
merely illustrative and are not intended to limit the scope of the
present invention. The computer systems may contain additional
components or may lack some illustrated components. For example, it
is possible that the characterization module can be implemented on
the non-portable computer, with the body-mounted computer replaced
by a thin context client such as a transmitter/receiver for
relaying information between the body-mounted input and output
devices and the non-portable computer. Alternately, the user may
not wear any devices or computers.
In addition, the body-mounted computer may be connected to one or
more networks of other devices through wired or wireless
communication means (e.g. wireless RF, a cellular phone or modem,
infrared, physical cable, a docking station, etc.), either with or
without support from other computers such as the computer 150. For
example, the body-mounted computer of a user can make use of output
devices in a smart room, such as a television and stereo when the
user is at home, if the body-mounted computer can transmit
information to those devices via a wireless medium or if a cabled
or docking mechanism is available. Alternately, kiosks or other
information devices can be installed at various locations (e.g., in
airports or at tourist spots) to transmit relevant information to
body-mounted computers within the range of the information
device.
Those skilled in the art will also appreciate that specialized
versions of the body-mounted computer and characterization module
can be created for a variety of purposes.
FIG. 2 illustrates an exemplary computer system 200 on which an
embodiment of the characterization module is executing. The
computer includes a memory 230, a CPU 210, a persistent storage
device 250 such as a hard drive, and input/output devices including
a microphone 222, a video camera 223, a computer-readable media
drive 224, such as a CD-ROM, drive, a visual display 225, a speaker
226, and other devices 228. The memory preferably includes the
characterization module 231, as well as information reflecting the
current state of the characterization module (characterization
module state) 232. The memory further contains software modules
233, 234, and 237 that consume attributes and are therefore context
clients, and software modules 235, 236, and 237 which provide
attributes and are therefore context servers. While items 231-237
are preferably stored in memory while being used, those skilled in
the art will appreciate that these items, or portions of them, can
be transferred between memory and the persistent storage device for
purposes of memory management and data integrity.
The facility preferably utilizes a plain-language, hierarchical,
taxonometric attribute nomenclature to name attributes. The
attribute names within the nomenclature are preferably specific so
that there is no ambiguity as to what they represent. The facility
preferably supports the extension of the nomenclature by adding new
attribute names that conform to the hierarchical taxonomy of the
nomenclature. The nomenclature preferably has attribute names
relating to the user, such as user.position, user.speed, and
user.direction providing information about the user's position,
speed, and direction, respectively. The nomenclature preferably
contains attribute names for various user moods, such as
user.mood.happiness, user.mood.anger, and user.mood.confusion. The
nomenclature preferably includes attribute names for user
activities, such as user.activity.driving, user.activity.eating,
and user.activity.sleeping. The nomenclature preferably includes
attribute names for user physiology values, such as
user.physiology.pulse, user.physiology.body_temperature, and
user.physiology.blood_pressure. The nomenclature preferably
includes attribute names for similar attributes of people other
than the user, such as person.John_Smith.mood.happiness. The
nomenclature preferably includes attribute names for aspects of the
computer system or "platform." For example, the nomenclature
preferably includes attribute names for aspects of the platform's
user interface, such as
platform.user_interface.oral_input_device_availability and
platform.user_interface.visual_output_device_availability. The
nomenclature preferably includes attribute names for attributes
relating to the central processing unit, or "CPU," of the platform,
such as platform.cpu_load and platform.clock_speed. The
nomenclature preferably also provides attribute names for aspects
of the local environment, such as environment.local.time,
environment.local.temperature, and
environment.local.ambient_noise_level. The nomenclature preferably
also includes attribute names for remote environments, such as
environment.place.chicago.time and
environment.place.san_diego.temperature. The nomenclature
preferably further provides attribute names relating to specific
applications. For example, the nomenclature preferably provides
attribute names for aspects of an electronic mail application, such
as application.mail.available,
application.mail.new_messages_waiting, and
application.mail.messages_waiting_to_be_sent. In this manner, the
attribute nomenclature used by the facility provides effective
names for attributes relating to the user, the computer system, and
the environment. Additional detail on the attribute nomenclature
utilized by the facility is provided in U.S. patent application
Ser. No. 09/724,893, entitled "Supplying User Context Data With
Dynamically Specified Suppliers and Consumers," which is hereby
incorporated by reference in its entirety.
FIG. 3 is a data flow diagram showing a sample exchange of
attributes performed by the characterization module. The diagram
shows characterization module 300, as well as five other software
modules, 310, 320, 330, 340, and 350. Software modules 310, 320,
and 330 are said to be context servers, in that they provide
attributes to the characterization module. For example, context
server 330 provides an user.in_region attribute 331. It can be seen
that context servers may provide more than one attribute. For
example, context server 320 provides a user.location attribute 321,
and an user.elevation attribute 322. It can further be seen that a
single attribute may be provided by more than one context server.
For example, context server 310 provides user.location attribute
311, while context server 320 provides user.location attribute 321.
The characterization module preferably provides functionality for
mediating between these two separate instances of a user.location
attribute when the user.location attribute is requested by a
context client.
Software modules 330, 340, and 350 are said to be context clients
because they consume attributes. For example, context client 340
consumes user.location attribute 341. It can be seen that certain
software modules may act both as a context server and as a context
client. For example, software module 330 is both a context server
and a context client, as it provides the user.in_region attribute
331, as well as consuming a user.location attribute 332. It can
also be seen that a context client consumes more than one
attribute. For example, context client 350 consumes both
user.in_region attribute 351 and user.elevation attribute 352. To
determine which attributes are currently available, any of the
context clients may request that the characterization module
enumerate the available attributes. In response to such a request,
the characterization module would enumerate the user.location
attribute, the user.location attribute, and the user.in_region
attribute. Additional preferred embodiments permit context clients
to otherwise limit attribute enumeration requests. For example, a
context client may request enumeration of all user interface
attributes by specifying the wildcard-expanded attribute name
platform.user_interface.*.
The characterization module preferably implements the API functions
described in detail below in order to obtain attribute values from
context servers and provide them to context clients. While these
functions are preferably exposed via Microsoft Component Object
Module ("COM") interfaces, those skilled in the art will appreciate
that they could be made available to context servers and context
clients through a variety of other mechanisms, including a number
of different function-calling and message-passing invocation
schemes.
LaunchContextServer
Any application can launch a context server that is not already
running by calling this function, passing the following parameter:
Context Server Identifier--A filename, COM object, or other
identification method that unambiguously identifies the context
server and exposes a mechanism for launching it.
This function returns an error if the requested context server is
not found, and returns an error if the requested context server is
already running.
Each context server has an associated startup behavior, which
specifies whether or not the context server is automatically
launched when the characterization module launches. Context servers
installation application or the characterization module's control
panel applet may be used to change the startup behavior.
RegisterContextServer
When a context server launches, it calls this function to notify
the characterization module of its intent to provide attribute
instances, passing the following parameters: Context Server Name--A
name that conforms to attribute naming specifications and uniquely
identifies the context server. Version--A floating point number
that corresponds to the version of the context server. Installation
Date--The date and time that the context server was installed.
Filename--The context server's main filename expressed as an
absolute pathname. Request Handler--A reference to a context server
interface that accepts messages from the characterization module to
the context server. This information is not available to external
modules.
If the registration request includes a context server name that is
already in use, the characterization module returns an error and
does not register the context server.
FIG. 4 is a data structure diagram showing a context server table
that maintains a portion of the state of the characterization
module. When the RegisterContextServer function is called, the
characterization module preferably adds a row to the context server
table corresponding to the registered context server. The context
server table 400 contains rows 401-403, each corresponding to a
registered context server. Each row contains a context server name
field 411 containing the name of the context server, a version
field 412 identifying the version of the context server, an
installation date 413 identifying the date on which the context
server was installed on the computer system, a filename 414
identifying a primary file in the file system representing the
context server, and a request handler field 415 containing a
reference to a request handler function on the context server that
may be called by the characterization module to request evaluation
of one or all of the attributes provided by the context server. The
characterization module preferably adds a row to the context server
table when the LaunchContextServer function is called. For example,
when the location_region_analysis context server calls the
LaunchContextServer function, the characterization module
preferably adds row 403 to the context server table. The contents
of row 403 indicate that version 1.00.315 of the
location_region_analysis context server, installed on Feb. 10, 2000
and having file name l_r_a.exe is registered with the request
handler referenced in the request handler field 415 of row 403.
CreateAttributeInstance
Context servers may create an attribute instance at any time by
calling this function, passing the following parameters: Context
Server Name--A name that is unique to the requesting context
server. This name should be the same for all attributes that the
context server creates. In some embodiments, this parameter is
implicit in each call to this function, and need not be explicitly
passed. Attribute Name--The name of the attribute. Data Type--The
type of data in which the attribute's value and uncertainty are
expressed. Format Version--The number of the format version in
which the value is expressed. Request Handler--A reference to the
context server function that processes attribute requests from the
characterization module. The characterization module may also send
messages to the context server via this function. A single request
handler may be used for multiple attributes. In an alternative
embodiment, the Request Handler parameter may be specified only
during context server registration, rather than during attribute
instance creation, or during either activity. Startup
Behavior--Specifies whether or not the context server should be
loaded automatically at startup. This parameter is optional. If
included, it supercedes any previous setting for the requesting
context server. If the startup behavior is never specified, the
characterization module is not responsible for launching the
context server. In an alternative embodiment, the Startup Behavior
parameter may be specified only during context server registration,
rather than during attribute instance creation, or during either
activity.
This function returns an error if the name matches that of an
attribute that the context server has already created. If another
instance of the attribute already exists and has the same format
version, this function returns an error if the data type does not
match that of the existing attribute.
FIG. 5 is a data structure diagram showing an attribute instance
table that maintains a portion of the state of the characterization
module. The attribute instance table contains a row for each
attribute instance created by a context server. When a context
server calls the CreateAttributeInstance function, the
characterization module preferably adds a row to the attribute
instance table. The attribute instance table 500 contains rows
501-504, each corresponding to a different attribute instance. Each
of these rows contains the following fields: an attribute name
field 511 containing the name of the attribute, a context server
name field 512 identifying the context server that created the
attribute instance, a value field 513 containing the value of the
attribute last provided by the context server, and uncertainty
field 514 identifying the level of uncertainty of the value, a
timestamp 515 indicating the time at which the value is effective,
and a units field 516 identifying the units for the value and the
uncertainty. For example, row 501 indicates that an instance of the
user.location attribute from the gps context server has the
effective time of 13:11:04.023 on Feb. 22, 2000. Its value is
47.degree. 36.73' N, 122.degree. 18.43' W degrees and minutes, with
an uncertainty of 0.degree. 0.09'. It should be noted, as shown,
the user's location, expressed in terms of latitude and longitude,
is maintained in a single attribute. In alternative embodiments,
such a location could be maintained in a larger number of
attributes. For example, rather than being maintained in a single
user.location attribute, such a location could be distributed
across four separate attributes: user.location.latitude.degrees,
user.location.latitude.minutes, user.location.longitude.degrees,
and user.location.longitude.minutes. The characterization module
preferably adds row 504 to the attribute instance table when the
location_region_analysis context server calls the
CreateAttributeInstance function for the user.in_region
attribute.
RegisterContextClient
Each context client registers with the characterization module,
passing the following parameters: Name--A name for the context
clients used for all attribute registrations for a particular
context client. If the context client also acts as a context
server, it preferably uses the identical name for context server
registration, though may use a different name. Message Handler--A
reference to a context client function that processes messages from
the characterization module, such as notifications that attributes
are destroyed or the characterization module is shutting down.
The first time a context client registers, it provides a non-null
message handler. Subsequent calls by that context client may
provide a new message handler that replaces the previous one.
FIG. 6 is a data structure diagram showing a context client table
that maintains a portion of the state of the characterization
module. The context client table 600 contains rows 601-603, each
corresponding to a registered context client. Each row contains a
context client name field 611 identifying the name of the
registered context client, as well as a message handler field 612
containing the reference to a message handler provided by the
context client for processing messages from the characterization
module. The characterization module preferably adds a row to the
context client table for each context client that calls the
RegisterContextClient function. For example, the characterization
module preferably adds row 603 when the region_analysis context
client calls the RegisterContextClient function. Added row 603
contains a reference to the message handler for the region_analysis
context client.
EnumerateAttributes
Context clients call this function to request a listing of
attributes that meet certain criteria, passing the following
parameter: Source--The name of the context server providing the
attributes that the context client is requesting. If supplied, the
characterization module returns all attributes from the
corresponding context server. If not supplied, the characterization
module returns all attributes.
This function returns the following information to the calling
context client: Attributes--A list of the attributes that meet the
request's criteria. If no attributes meet the criteria, the list is
empty. If an attribute meets the criteria but its source-prohibits
the context client from seeing the attribute, it is not included in
the list.
If a source is specified and not found, the characterization module
returns an error to the context client. In additional preferred
embodiments, other parameters may be included to limit the set of
attributes that are enumerated.
RegisterToConsumeAttributeOrInstance
A context server calls this function for each attribute or
attribute instance that it will be requesting, passing the
following parameters: ContextClientName--The context client's name
AttributeName--The name of the attribute that the context client is
requesting to consume. Source--The context server whose instance of
this attribute the context client is registering to consume. If
blank, the request constitutes a request to consume a mediated
attribute, rather than an attribute instance.
Context clients may register for attributes at any time. Requests
for nonexistent attributes produce an error. Requests are not
persistent, so the context client must register again to consume
the attribute or attribute instance when it becomes available.
FIG. 7 is a data structure diagram showing an attribute or instance
registration table that maintains a portion of the state of the
characterization module. The attribute or instance registration
table contains rows 701-704, each corresponding to a different
registration that a context client has made for an attribute or an
attribute instance. Each row contains a context client name field
711 indicating the name of the context client registering to
consume the attribute or attribute instance, an attribute name
field containing the attribute name for the attribute or attribute
instance, and a context server name field 713 that, for attribute
instance registrations contains the name of the context server
providing the instance, which is blank for attribute registrations.
For example, row 704 indicates that the location map context client
has registered to consume the instance of the user.in_region
provided by the region_analysis context server.
GetAttribute
Context clients call this function to request an attribute value,
passing the following parameters: Name--A name identifying the
attribute. Source--The name of the context server from which to
obtain the requested attribute. If no Source is specified, the
characterization module assumes the attribute may come from any
source, and it uses an attribute mediator to select one. Attribute
mediator--The name of the selection method that it would like used
to select the attribute from multiple instances. If no attribute
mediator is provided, the characterization module's default method
is used. If a source and an attribute mediator are provided, the
mediator is ignored. The characterization module preferably
provides attribute mediators such as the following: a mediator that
selects the first attribute instance that was created, a mediator
that selects the last attribute instance that was created, a
mediator that selects the first attribute instance to be provided
in response to a request for evaluation, a mediator that selects
the attribute instance having the lowest level of uncertainty, a
mediator that selects the attribute instance having the newest data
value, a mediator that calculates the average of the available
attribute instances, a mediator that selects the most common of the
attribute instances, a mediator that allows the user to select
among the attribute instances, and mediators that select an
attribute instance whose confidence level, as adjusted for
attenuation over the age of the data at a variety of rates, is the
highest. Those skilled in the art will appreciate that additional
types of attribute mediators may also be employed by the
characterization module and requested by context clients. Age--An
expression of the maximum age of the attribute information. If the
request is made for a specific attribute instance by specifying a
source, then only that instance is checked, and if too old, it is
freshened. If no source is specified and multiple instances are
present, the characterization module applies the attribute mediator
to those that satisfy the age requirement. If no instances satisfy
the age requirement, all instances are freshened prior to the
application of the attribute mediator. Timeout--A period of time
within which the characterization module should return the
attribute. If the attribute is not evaluated within this time, the
characterization module sends an error message to the context
client. The resulting return values are those of the most recent
valid evaluation, or null if no valid data are available. A timeout
value of zero instructs the characterization module to wait
indefinitely for a response. Supplemental Properties--The context
server may also return to the characterization module names and
values for supplemental properties associated with the attribute
instance. For example, some supplemental properties may include
security information used to determine which context clients may
receive attribute instance, as well as additional information
further characterizing the attribute instance.
If the request timeout is exceeded and the characterization module
subsequently responds to the request, the returned value replaces
the current most recent value cached in the characterization
module. If an error is returned after the timeout period, it is
ignored. The characterization module preferably does not send
additional information to the context client that initiated the
request.
This function returns the following to the calling context client:
Name--A string that identifies the attribute. Value--The quantity
of the attribute. Uncertainty--A quantity that represents the range
of likely values around Value that the attribute is likely to have.
The contents of the Uncertainty property depend upon what type of
information is stored in Value. The Uncertainty property
characterizes the extent to which the attribute value may differ
from the real quantity being measured, based upon factors
including--but not limited to--the precision of measuring apparatus
used to measure the quantity, the conversion of continuous
quantities to discrete values in the measurement process, random
fluctuations, temporal variations, systematic errors, and
measurement latency. Timestamp--A timestamp that represents the
effective age of the data. In particular, the timestamp specifies
the time at which the attribute value would have been valid had it
been measured directly at that moment, irrespective of whether the
attribute value was actually measured at that time. Units--The
units of measure in which the Value and Uncertainty have been
expressed. Source--A reference to the object that created and owns
the instance of the attribute, usually a context server. If the
attribute comes from a condition or a condition monitor, the source
is the source of the condition or condition monitor. Some
attributes that refer to the characterization module or that are
monitored by the characterization module have the characterization
module as the source. Attribute mediator--The name of the selection
method that was used to select the attribute from multiple
instances. If no attribute mediator was used (either because only
one instance of the attribute was available or because a source was
specified), the attribute mediator is left blank. Format
Version--The version of the attribute's format specification.
Flags--Not in use at this time. Supplemental Properties--Where the
context server has provided supplemental properties, they are
returned to the context client, except where the supplemental
properties are designated to not be provided to context clients.
Reference to Context Server's Callback Function--Optional: The
characterization module may return to the context client a direct
reference to the context server that provided the returned
attribute instance, enabling the context client to call the context
server directly in the future to get a new value for the
attribute.
This function returns an error to the calling context client if the
requested attribute, requested source, or the requested mediator
does not exist or if its value is, unavailable. Attributes whose
values are unavailable are ignored if other instances of the
attribute satisfy the request made by the context client.
FIG. 8 is a flow diagram showing the steps preferably performed by
the characterization module when the GetAttribute function is
called. In step 801, if the requested attribute exists, then the
facility continues in step 803, else the facility continues in step
802 to return an "attribute not found" error. In step 803, if a
single instance of the attribute was requested, then the facility
continues in step 804, else the facility continues in step 811. In
step 804, if the requested instance exists, then the facility
continues in step 806, else the facility continues in step 805 to
return an "attribute instance not found" error. In step 806, if the
age criterion specified for the attribute request is satisfied,
then the facility continues in step 807 to return the requested
attribute instance, else the facility continues in step 808 to
"freshen" the attribute instance by calling the appropriate context
servers' request handler to request evaluation of the attribute
instance. In step 809, if the age criterion is satisfied by the
freshened attribute instance, then the facility continues in step
807 to return the freshened attribute instance, else the facility
continues in step 810 to return the freshened attribute instance
with an "age not satisfied" error.
In step 811, where a single attribute instance was not requested,
if any registered instances of the attribute satisfy the age
criterion, then the facility continues in step 816, else the
facility continues in step 812. In step 812, the facility freshens
all registered instances of the requested attribute. In step 813,
if any of the attributes freshened in step 812 satisfy the age
criterion, then the facility continues in step 816, else the
facility continues in step 814. In step 814, the facility applies
the requested attribute mediator to select one instance, or
otherwise derive a value from the registered instances. In step
815, the facility returns the instance with an "age not satisfied"
error.
In step 816, where one or more instances satisfy the age criterion,
if more than one instance satisfies the age criterion, then the
facility continues in step 817, else the facility continues in step
807 to return the attribute instance that satisfies the age
criterion. In step 817, the facility applies the requested
attribute mediator to select one instance from among the instances
that satisfy the age criterion, or to otherwise derive a value from
the instances that satisfy the age criterion. After step 817, the
facility continues in step 807 to return the value produced by the
mediator.
The characterization module requests attributes from a context
server by calling the request handler registered by the context
server, passing the following parameters: Attribute Name--The name
of the attribute being requested. Timeout--The timeout period that
the context server is expected to fulfill.
The context server is expected to satisfy the request within the
timeout period with the following information: Value--The quantity
of the attribute. Uncertainty--A quantity that represents the range
of likely values around Value that the attribute is likely to have.
The contents of the uncertainty property depend upon what type of
information is stored in Value. The uncertainty is required and is
expressed in the same units and format as the value. Timestamp--A
timestamp that represents the effective age of the data. This age
reflects the point in time when the value is most accurate. It is
the responsibility of the context server to determine how the
timestamp relates to those of attributes that it uses. The
timestamp is required, and is preferably determined with the
computing platform's clock to facilitate easy comparison in context
clients. Units--The units of measure in which the Value and
Uncertainty have been expressed as a predefined set of allowable
units, from among a predetermined set of allowable units. The units
parameter is required. Format Version--The version of the format
specification used to express the attribute's value and
uncertainty.
If the context server is able to determine that the request cannot
be answered, it returns an error to the characterization module.
For instance, the context server may be asking a physical sensor
for data, and the physical sensor is not responding.
If the context server cannot provide an attribute because it
received an error message from an attribute that it queries, it
returns the error message that it received.
When a call to this function necessitates the reevaluation of an
attribute instance, the characterization module preferably
substitutes that value in the corresponding row of the attribute
instance table, thereby caching the attribute instance for possible
future use. FIG. 9 is a data structure diagram showing updated
contents of the attribute instance table. It can be seen in
attribute instance table 900 that, upon reevaluation by the ips
context server of its instance of the user.elevation attribute, the
characterization module replaced the former contents of the value,
uncertainty and timestamp field of row 903, shown in FIG. 7, with
the values resulting from the reevaluation shown in FIG. 9.
GetAllAttributeInstances
Context clients call this function to request all instances of a
particular attribute. This function uses the same parameters as
GetAttribute, except that the attribute source is omitted. This
function returns the same information for each attribute
instance.
In one embodiment, this function is separate from the GetAttribute
function. In an alternative embodiment, this function is omitted
and the GetAttribute function is called without specifying the
attribute source parameter in order to request all instances of a
particular attribute.
CompleteContextServerEvaluation
To force a context server to calculate all of its output attributes
at the same time, a context client calls this function, passing the
following parameters: Context Server Name--An identifier of the
context server of interest. Timeout--A period of time within which
the characterization module should successfully force a complete
evaluation. If the context server's attributes are not completely
evaluated within this time, the characterization module sends an
error message to the context client.
When this function is called, it in turn calls the request handler
for the identified context server, requesting complete evaluation
of the context server's attributes by specifying a special value
for the AttributeName parameter. In response, the context server
evaluates all of its attributes and provides them to the
characterization module delaying other requests until it has
finished. If the context server uses other attributes to evaluate
its own, it requests fresh versions of these attributes, but it is
neither required to or prohibited from requesting complete
evaluation.
This function returns the following to the calling context client:
Attributes--The attributes that were simultaneously evaluated
including all of their constituent information as specified in the
GetAttribute section. Note that the attribute source need not be
repeated for each attribute.
This function returns an error if the request either timed-out or
there was no context server with the specified name.
The characterization module possesses several attributes of its own
that may be of interest to context clients and context servers.
Read-only parameters are surfaced as attributes identical to those
created by other context servers, except that the owner of these
attributes is the characterization module itself. Several
adjustable items require two-way information flow and thus have
their own interfaces. In an alternative embodiment, adjustable
items are exposed as attributes.
GetChatacterizationModuleAttribute
Context clients call this function to request attributes containing
information about the characterization module, passing a parameter
identifying the requested attribute. The available items are
attributes for which the characterization module is the creator and
owner; otherwise they behave identically to all other attributes.
characterization module attributes are visible to all context
clients. The following read-only characterization module attributes
may be requested: Version--Contains a description of the
characterization module version. Path--A string containing the
absolute path within which the characterization module has been
installed, in the proper format for the computing platform.
Time--The local time as maintained by the computer's clock.
Date--The date as maintained by the computer's clock. Default
Timeout--Some requests require polling context servers for
attribute information. The characterization module sends an error
to the requesting context client if the context server does not
respond within a specified time interval. If the context client has
not specified this interval with its request, the characterization
module's default value is used. A timeout value of zero instructs
the characterization module to wait indefinitely for a response. No
parameters are necessary to read the default timeout setting, and
such requests result in an immediate response from the
characterization module with that information. The default timeout
may preferably be changed by the user via a characterization module
control application/control panel applet. In additional
embodiments, the default attribute mediator may be changed in
another manner, such as under the control of a program other than
the characterization module. Default Attribute Mediator--Context
clients can read the characterization module's default attribute
mediator. No parameters are necessary to read the default attribute
mediator, and the characterization module returns the attribute
mediator's name. The default attribute mediator may preferably be
changed by the user via a characterization module control
application/control panel applet. In additional embodiments, the
default attribute mediator may be changed in another manner, such
as under the control of a program other than the characterization
module.
In one embodiment, this function is separate from the GetAttribute
function. In an alternative embodiment, this function is omitted
and the GetAttribute function is called in order to request a
characterization module attribute.
CreateCondition
Context clients call this function to create a condition to check a
relationship between an attribute and a value or between two
attributes, passing the following: Name--A name for the condition.
This name must be unique among all conditions created by the same
context client. 1.sup.st Logical Parameter--An attribute name
identifying an attribute, an attribute name and source identifying
an attribute instance, or a condition name identifying a condition.
2.sup.nd Logical Parameter--An attribute name identifying an
attribute, an attribute name and source identifying an attribute
instance, or a condition name identifying a condition. Value--A
value for attribute comparison. If an attribute is provided as the
2.sup.nd logical parameter, the value is ignored. Logical
Operator--One of a predefined set of logical operators. The allowed
operators depend upon whether the characterization module is asked
to compare attributes or conditions as shown in Table 1 below.
TABLE-US-00001 TABLE 1 List of Logical Operators for Conditions
Attributes Conditions > AND < OR = XOR >= NOR <=
NOT
Conditions may compare an attribute with another attribute, and
attribute with a value, or a condition with another condition.
These combinations are listed below in Table 2.
TABLE-US-00002 TABLE 2 Parameter Usage for Conditions 1.sup.st
Parameter 2.sup.nd Parameter Action Attribute Name <none>
Compares attribute to value Attribute Name Attribute Name Compares
attributes to each other Condition Name Condition Name Compares
conditions to each other
This function returns an error if the requested name is already in
use by another condition that was created by the calling context
client. An error is returned if the referred to attributes or
conditions do not exist. An error is returned if an attribute is
requested along with a condition or vice-versa.
FIG. 10 is a data structure diagram showing a condition table that
contains a portion of the state of the characterization module.
Condition table 1000 has a row for each condition created by a
context client. Row 1001 contains a condition name field 1011
containing the name of the condition, a context client name 1012,
identifying the context client that created the condition, a first
logical parameter field 1013 and a second logical parameter field
1014 identifying, attributes or other conditions that are compared
by the condition, a comparison value 1015 that specifies a value to
which the first logical parameter is compared if no second logical
parameter is listed, and a logical operator 1016, identifying the
logical operator to be applied in the comparison. The
characterization module preferably adds row 1001 to condition table
1000 when the region_analysis context client creates the
in_region_true condition to indicate whether the user is presently
within a special region. Added row 1001 indicates that the
in_region_true condition was created by the region_analysis context
client, and has first logical parameter user.in_region, no second
logical parameter, comparison value TRUE, and logical operator
"=".
EvaluateCondition
A context client calls this function to query conditions that it
has created passing the following parameters: Name--The name of the
condition. Timeout--A period of time within which the
characterization module should have successfully evaluated the
condition.
This function returns the following to the calling context client:
Value--A Boolean expression resulting from the evaluation of the
condition.
This function returns an error if the condition requests a
non-existent attribute, the requested condition does not exist, or
the timeout is exceeded.
When this function is called for a particular condition, the
facility preferably uses the information in the corresponding row
of the condition table to evaluate the condition. For example, when
this function is called for the in_region_true condition, the
facility preferably uses information row 1001 of condition table
1000 shown in FIG. 10 to evaluate this condition.
CreateConditionMonitor
A context client calls this function to create a condition monitor
to monitor for a change in a condition and be notified when it
occurs, passing the following parameters: Name--The name of the
condition monitor. Condition--The name of the condition that
triggers the condition monitor. Behavior--Specifies when the
condition monitor triggers. The condition monitor may be triggered
when the condition becomes true, becomes false, or when it changes
state in either direction. Frequency--The time between subsequent
checks for triggering of the condition monitor. This value must be
non-zero. Trigger Handler--A reference to a context client
procedure that the characterization module notifies when the
condition monitor is triggered.
An error is returned if the name is already in use by another
condition monitor from the calling context client.
FIG. 11 is a data structure diagram showing a condition monitor
table that maintains a portion of the state of the characterization
module. Condition monitor table 1100 has a row 1101 corresponding
to a condition and containing each of the following fields: a
condition monitor name field 1111 containing the name of the
condition monitor; a context client name field 1112 containing the
name of the context client that created the condition monitor; a
condition name field 1113 that contains the name of the condition
monitored by the condition monitor; a behavior field 1114 that
indicates whether the condition monitor is triggered when the
condition becomes true, when it becomes false, or when it changes
value in either direction; a frequency field 1115 showing the
frequency with which the condition monitor evaluates the condition;
a condition last evaluated field 1116 showing the time at which the
condition monitor last evaluated the condition; a trigger handler
reference 1117 that identifies a trigger handler function of the
context client that is to be called when the condition monitor is
triggered; and a stopped field 1118 that indicates whether the
context client has suspended operation of the condition monitor.
The condition monitor preferably adds row 1101 to the condition
monitor table when the region_analysis context client creates the
region_boundary_crossed condition to notify the region_analysis
context client when the value of the in_region_true condition
changes, indicating that the user has entered or left the special
region. Row 1101 indicates that the region_boundary_crossed
condition monitor was created by the region_analysis, context
client, is based upon the in_region_true condition, monitors for
both TRUE and FALSE behavior, is evaluated every 30 seconds, was
last evaluated at 13:11:29.101 on Feb. 22, 2000, has the trigger
handler referenced in field 1117 of row 1101, and is not presently
stopped.
StopConditionMonitor
A context client calls this function to temporarily suspend the
operation of a condition monitor, passing the following parameter:
Name--The name of the condition monitor.
This function returns an error to the calling context client if the
name does not correspond to an existing condition monitor created
by that context client.
FIG. 12 is a data structure diagram showing updated contents of the
condition monitor table. It can be seen from stopped field 1218 of
row 1201 in condition monitor table 1200 that the region_analysis
context client has stopped, or suspended the operation of, the
region_boundary_crossed condition monitor, perhaps in response to
the observation that the user is now asleep and his or her location
will remain constant.
StartConditionMonitor
A context client calls this function to resume operation of a
stopped condition monitor, passing the following parameter:
Name--The name of the condition monitor.
This function returns an error to the calling context client if the
name does not correspond to an existing condition monitor created
by that context client.
When the StartConditionMonitor function is called, the facility
preferably changes the contents of the stopped field 1118 from
"yes" as shown in FIG. 11 to "no" as shown in FIG. 12, so that the
characterization module resumes operation of the condition
monitor.
RemoveConditionMonitor
Context clients call this function to remove a condition monitor
that it has created, passing the following parameter: Name--The
name of the condition monitor.
This function returns an error to the calling context client if the
name does not correspond to an existing condition monitor created
by the calling context client. If the condition monitor is active
when this function is called, this function automatically stops the
condition monitor prior to removing it.
When this function is called, the characterization module
preferably deletes the row of the condition monitor table
corresponding to the condition monitor. For example, if this
function is called for the region_boundary_crossed condition
monitor, the characterization module preferably deletes row 1201 of
condition monitor table 1200 shown in FIG. 12.
RemoveCondition
A context client calls this function to remove a condition that it
owns, passing the following parameter: Name--the name of the
condition to be removed.
An error is returned if the name does not correspond to an existing
condition created by the calling context client. The
characterization module returns an error if other conditions or
condition monitors rely upon the condition, and the condition is
not removed.
When this function is called for a particular condition, the
characterization module preferably deletes the corresponding row
from the condition table. For example, when this function is called
for in_region_true condition the facility preferably deletes row
1001 from condition table 1000 shown in FIG. 10.
In the foregoing, a preferred embodiment is described in which
conditions and condition monitors are created separately. In an
alternative preferred embodiment, conditions and condition monitors
are created together as a single entity, with a single API function
call.
UnregisterToConsumeAttributeOrInstance
A context server calls this function to unregister to consume an
attribute or attribute instance that it is registered to consume,
passing the following parameters: Context Server Name--The name of
the context server. Attribute Name--The name of the attribute for
which the context client is unregistering. Source--For requests to
unregister to consume an attribute instance, contains the name of
the context server providing the attribute instance. For requests
to unregister to consume an attribute, is blank.
This function removes the row corresponding to the specified
attribute or instance registration from the attribute or instance
registration table.
This function returns an error if the attribute or instance
registration table does not contain a row corresponding to the
specified registration.
UnregisterContextClient
Context clients may unregister themselves at any time. Before
calling this function, context clients are expected to first remove
all conditions, condition monitors, and attributes that pertain to
the registration they are ending, parsing the following: Context
Client Name--Name of the context client to unregister.
Unregistration of a context client results in the removal of all
remaining conditions, condition monitors, and attribute consumption
registrations that it owns.
The characterization module may ask the context client to
unregister. Such requests require no parameters. The context client
responds to such a request by calling this function within a
reasonable period of time. If such acknowledgement is not made, the
characterization module preferably removes the context client
registration and all of its conditions and condition monitors
automatically.
When this function is called for a particular context client, the
characterization module preferably deletes the corresponding row
from the context client table. For example, when this function is
called for the region_analysis context client, the facility
preferably deletes row 603 from context client table 600 shown in
FIG. 6.
CheckAttributeInstanceDependencies
To determine whether there are context clients using one of its
attribute instances, a context server calls this function, passing
the following parameter: Attribute--The name of the attribute.
Context Server Name--The name of the calling context server.
This function returns the following to the calling context server:
Number--The number of context clients that are registered for the
attribute instance named in the request. This includes all context
clients that have registered for the context server's specific
instance as well as those that have registered for the attribute
for which there is only one instance. This does not include
registrations for an attribute for which there, are additional
context server's able to satisfy the context clients' requests.
This function returns an error if the requested attribute instance
does not exist.
When this function is called, it preferably first refers to the
attribute or instance registration table to count how many context
clients have registered specifically, for the calling context
server's instance of the attribute. The function further identifies
any registrations for this attribute from any context server, i.e.,
rows of the attribute or instance registration table containing the
attribute name of this attribute instance and no context server
name. For these identified rows, the function consults the
attribute instance table to determine whether instances of this
attribute other than the one provided by the calling context server
are present in the table. If not, the function also counts the
number of context clients registered to consume the attribute from
any context server.
RemoveAttributeInstance
Context servers call this function to remove the instances of
attributes that they have created, passing the following parameter:
Name--The name of the attribute to remove.
This function returns an error if the requested name does not
correspond to an attribute that the context server may remove.
This function notifies context clients registered for this
attribute instance that it is no longer available. Context clients
that register for any one of multiple instances of an attribute are
only notified when the last instance of the attribute is removed.
If conditions or condition monitors rely upon the attributes that
are being removed, their owners are notified, and the conditions
and rules are removed.
When this function is called for a particular attribute instance,
the characterization module preferably removes the corresponding
row from the attribute instance table. For example, when the
location_region_analysis context, server calls this function for
its instance of the user.in_region attribute, the characterization
module preferably deletes row 504 from attribute instance table 500
shown in FIG. 5.
UnregisterContextServer
A context server may unregister at any time by calling this
function. Calling this function requires no additional
parameters.
Unregistration causes the characterization module to remove any
remaining attribute instances belonging to that context server
(thereby requiring the characterization module to notify any
registered context clients) prior to actually releasing the context
server.
The characterization module may ask the context server to
unregister, in which case the context server is expected to
acknowledge the request by requesting unregistration. Failure of
the context server to acknowledge the request within a reasonable
period of time causes the context server and its attributes to be
removed automatically.
The user is preferably able to control several values that affect
characterization module function using a windows control panel
applet dedicated to the characterization module. The parameters
under user control include the following: Default Timeout--See
Default Timeout section. Default Attribute Mediator--See. Default
Attribute Mediator section. Context Server Listing--A list of all
currently registered context servers and whether or not each is
automatically started at characterization module startup. Context
Client Listing--A list of all currently registered context clients
and the attributes for which they have registered.
Users can enter a default timeout value. This value must be greater
than or equal to zero.
Users can select the default attribute mediator from a list of
available mediators.
Users can refresh the display of context servers and context
clients at any time.
When UnregisterContextServer function is called by a particular
context server, the characterization module preferably removes the
corresponding row from the context server table. For example, when
this function is called for the location_region_analysis context
server, the characterization module preferably removes row 403 from
context server table 400 shown in FIG. 4.
In the foregoing, the facility is described as being implemented
using a characterization module that is called by context servers
and context clients, caches attribute values, and maintains status
information about the operation of context servers and context
clients. In an alternative preferred embodiment, however, the
facility operates without the use of such as characterization
module. In this embodiment, context servers communicate directly
with context clients.
FIG. 13 is a data flow diagram showing the operation of the
facility without a characterization module. It can be seen in FIG.
13 that context servers 1310, 1320, and 1330 provide attributes
directly to context clients 1330, 1340, and 1350. For example, it
can be seen that context server 1320 provides a user.elevation
attribute 1322 directly to context client 1350. In this embodiment,
the context client may itself cache attribute values recently
obtained from a context server. Further, in this embodiment,
context clients may themselves interrogate context servers for an
enumeration of their attributes, and mediate between attribute
instances provided by different context servers. For example,
context client 1340 may mediate between the instance 1311 of the
user.location attribute provided by context server 1310 and the
instance 1321 of the user.location attribute provided by context
server 1320.
Additional embodiments of the facility support supplemental
properties for attribute instances that are supplied by the context
server supplying an attribute instance, maintained by the
characterization module, and, in some cases, returned to context
clients requesting a value of the corresponding attribute.
FIG. 14 is a data structure diagram showing an attribute instance
property table that maintains a portion of the state of the
characterization module. Each row in the attribute instance
property table 1400 corresponds to a supplemental property provided
by a context server for an attribute instance it provides. Each row
contains an attribute name field containing the attribute name for
the attribute instance, a context server name 1402 containing the
name of the context server providing the attribute instance, a
property name 1403 containing a property name for the property, and
a property value field 1404 containing the value of the property.
For example, row 1401 shows that with its instance of the
user.location attribute, the ips context server has also provided a
security_token property having the value 5A637AR. Some supplemental
properties are preferably provided to context clients calling the
GetAttribute function for the attribute instance. Other
supplemental properties, such as the security_token property,
represented by row 1401, are preferably withheld from context
clients for the exclusive use of the characterization module. For
example, the characterization module preferably uses the
security_token property to determine whether a particular context
client should be permitted to obtain values of the user_location
attribute instance provided by the ips context server by calling
the GetAttribute function.
In additional preferred embodiments, the facility may operate with
a partial characterization module. Such a partial characterization
module may include various combinations of the functionalities of
routing communication between context servers and the context
clients that consume their attributes, caching attribute values,
enumerating available attributes, and providing attribute
mediation. In further preferred embodiments, the facility utilizes
a characterization module that constitutes a passive data store
that is shared between context servers and context clients. Context
servers access the data store to write attribute values, and
context clients access the data store to read attribute values.
In additional preferred embodiments, the facility may provide a
characterization module that implements a "push" information flow
model, in which, each time an attribute value provided by a context
server changes, the new value is automatically provided to context
clients. In some cases, context servers may push selected attribute
values. For example, context servers may push attributes whose
values are constant, attributes whose values change infrequently,
or attributes whose values are expensive to obtain. In further
preferred embodiments, the facility, provides a characterization
module that implements a "pull" information flow model, in which
attribute values are only obtained by the characterization module
from the context servers when they are requested by a context
client. In additional preferred embodiments, characterization
modules are provided that support a variety of other information
flow models.
It will be understood by those skilled in the art that the
above-described facility could be adapted or extended in various
ways. For example, the characterization module may be implemented
in computing devices other than wearable computers, including other
types of mobile computing devices, such as personal digital
assistants. The characterization module may further be implemented
on various types of stationary and/or distributed computing
devices, as well as non-traditional computing devices, such as
smart appliances. Further, rather than the attribute, context
server, context client, condition, and condition monitor names
discussed above, the facility may use other types of identifiers,
such as handles. While the foregoing description makes reference to
preferred embodiments, the scope of the invention is defined solely
by the claims that follow and the elements recited therein.
* * * * *
References